Lau (劉, Ryū; Chinese Pinyin: Liú) is a Chinese nobleman, the British branch manager of the Shanghai trading company "Kong-Rong," an operator of opium dens, the top official of the Chinese syndicate Qīng Bāng, and an Aristocrat of Evil.
In order for Lau to conduct business in England's "underworld," he must follow Ciel Phantomhive's orders to the letter. That being so, Ciel has left the administration of the Oriental quarter, the East End, and black-market docks to Lau.
Lau is a tall man with short black hair and dark brown eyes, which he almost never opens. Additionally, he has a blue dragon tattoo on his left arm.
Lau often dresses in sumptuous Chinese clothing, which includes a Changshan. He tends to keep his hands clasped and hidden in his "capacious" sleeves. Within said sleeves is a needle, which he describes as "an instrument of oriental medicine."
In 1887, Lau had long hair, which he wore in a braid.
Lau is a placid, even-tempered individual who is apt to make facetious remarks and act as though he is aware and well-informed of an important matter, only to later reveal that he is, in truth, clueless; Sebastian Michaelis believes that he simply chimes in whenever "he thought it appropriate." Moreover, he is frequently accompanied by the female attendants of the opium den he manages. He refers to his personal assassin, Ran-Mao, as his sister, although they are not related by blood.
Lau is an enigma; Baldroy once mused that he is uncomfortable around him, since he can never tell what he is thinking. Furthermore, Lau is, for the most part, unprincipled and mercenary. He curries favor with those he thinks will allow him and his business to advance and those who are ambitious, such as Ciel Phantomhive. He once suggested that he has no qualms about ingratiating himself with Scotland Yard, despite his mafia origins, so long as he can profit. Generally, he does not assist others without expecting payment in return; for instance, after rescuing Ciel and his household from Scotland Yard, he stated that he must be repaid "with interest." Moreover, he is averse to handouts "for the penniless" and the like; for that reason, he had Ciel and Sebastian work at the opium den during their temporary stay.
Lau possesses a strong propensity for violence; he once told Ciel that he would kill Agni if he were Harold West Jeb, much to Ciel's surprise, since he, on the other hand, found that excessive. While Ciel was willing to spare Harold and Mina, Lau had Ran-Mao terrorize both of them. Moreover, in his zeal to aid Sebastian in distracting Elizabeth Midford with a magic trick, which involved sticking swords in a chest Sebastian was in, Lau did so without delay or leniency and even immediately attacked from the top; Sebastian admitted that Lau had managed to inflict minor pain on him, a demon.
Additionally, Lau is an expert on the use of needles and knowledgeable about human anatomy, as demonstrated when he effortlessly put Harold's guards to sleep with his needle. He is not particularly fond of English dishes; to him, they taste "only of salt and pepper."
In only a few years, Lau managed to climb the ranks in Qīng Bāng and became a top official, receiving the sobriquet "Rising Dragon of the British Concession" in the process. He was then put in charge of The Bund in Shanghai.
Black Butler Arc
Lau engages in a meeting with Ciel Phantomhive, Chlaus, Angelina Dalles, Azzurro Vanel, Arthur Randall, and Diedrich. They discuss the issue of a malicious "rat" and the necessity of it being eradicated, implying that a drug-dealer is among them.
Red Butler Arc
At Ciel's London townhouse, Lau, with Angelina Dalles and Grelle Sutcliff, loot for tea leaves. Sebastian Michaelis accommodates them with tea, and they gather to discuss the recent string of murders so vicious that the killer was given the nickname "Jack the Ripper."
Lau points out that the murderer is definitely an "abnormal madman", and he questions if Ciel is daring enough to investigate the gruesome crime scene. He opts that they go right away, but when Angelina asks him for the location, he reveals that he, too, does not know where the crime scene is.
Consequently, Ciel suggests a certain place for information, and they arrive at the funeral parlor of Undertaker. When Undertaker appears out of his custom-made coffin, he frightens Lau, Angelina, and Grelle. They are directed to sit atop the coffins, and Undertaker agrees to share information, but only for some form of compensation. Lau asks him how much money he wants, and Undertaker vigorously approaches him to declare that he does not care for the Queen's money. Undertaker tells them to amuse him with the finest of laughs; Lau attempts to do so with a Chinese-influenced joke, but he fails. Sebastian later steps up, requests for them to wait outside, and forbids them from peeking inside. Lau and the others perceive strange noises coming from the funeral parlor, and afterwards, with Sebastian's permission, they enter to see Undertaker laughing wildly. Undertaker, then, reveals to them that all of Jack the Ripper's victims have had their internal organs removed with medical precision (Lau is also skeptical of his drink as Undertaker might have stored a kidney in the container).
On the carriage ride home, Sebastian is ordered to compile a list of suspects, and departs, impressing both Lau and Angelina. Ciel asserts that Sebastian will definitely be able to accomplish his mission and that he will have tea prepared for them as well. Lau comments that Ciel must be confident of Sebastian because since a long time ago, he has always been at the Earl's side, never leaving him- "like a shadow." Ciel then points out that Sebastian has not served him for even two years yet.
They return to Ciel's townhouse late because Grelle traveled the wrong way. Lau and Angelina are dumbfounded to see that Sebastian has already returned home first, with the tea and preparations finished. They listen with admiration as Sebastian reads off the blacklist of suspects. They chat, while having tea, and Sebastian, paying close regard to the conditions, narrows down the possibilities to Aleister Chamber.
That evening, they arrive at Aleister's party. Angelina and Grelle attend the party as themselves, Ciel as Angelina's niece from the countryside, Sebastian as Ciel's home tutor, and Lau as Angelina's lover. Afterward, Lau is obliged to fan Angelina as she indulges in luxury.
Sebastian, to serve as a distraction for Ciel, pretends to be a magician and asks the "random" gentleman, Lau, to assist him in the performance. Lau agrees, and Sebastian instructs that after he enters the cupboard, Lau is to tightly chain it up and then pierce the cupboard with several swords. Sebastian promises to come out alive, and after he goes inside the cupboard, Lau says he will not hold back. He immediately stabs from the top, bewildering the audience. He then swiftly applies the chains and thoroughly penetrates the cupboard with swords. Despite this, Sebastian steps out alive, and he and Lau receive the audience's passionate acclaim. Lau and Angelina praise Sebastian, and the former lightheartedly says that he had believed he killed Sebastian with his "mountain of needles". He curiously asks if there was some sort of trap, which causes Angelina to scold him for shoving all the swords at Sebastian without a thought. Nevertheless, Sebastian assures them both that he told them there were no tricks or traps.
The following day, they discover that Aleister is not "Jack the Ripper." Lau muses that if the suspect could not have carried out the murders, then others from the beginning are responsible for them. Later, Lau comments that the stormy night is "pitiful".
Subsequently, Lau attends Angelina's funeral and visits Ciel by her grave. He questions if he has revealed who the murderer was to the Queen, but Ciel states there was no reason to since the Jack the Ripper killings have stopped. Lau declares that this decision will cause him to "steadily sink into the mud" because of his refusal to seek help. Ciel retaliates by saying Lau's opium and intoxicants den, in time, will surely be closed by the police. Lau asserts that he can find a new business venture, as his interest in England and in Ciel is "far from exhausted"; he adds that he hopes Ciel will show him many more interesting things. They then part ways.
Indian Butler Arc
Ciel and Sebastian, after learning about the Anglo-Indian attacks, go to visit Lau in his opium den to see if he knows of any Indian hideouts. There, Lau is relaxing with Ran-Mao and several girls. Ciel scolds him to stop smoking opium and listen, and leaves East End to Lau since the number of people who move in and out of the street are under his management. They walk to East End to find the stronghold of Indians, but Lau soon admits he has lost track of where they are at while listening to Ciel's explanation of the incident.
They are then attacked and threatened by Indians, and Lau conceals himself on top of a roof and watches the ensuing fight and the arrival of Soma Asman Kadar and Agni. After Agni defeats all the Indians and subsequently departs with Soma, Lau praises Sebastian and Ciel and claims that he was hiding on the roof for the "right chance to jump in". He comments that Soma and Agni are definitely not from the East End due to their elegant apparel and accent.
Afterward, Lau returns with Ciel to the Phantomhive townhouse. There, they encounter Prince Soma and Agni again as the pair have decided to stay with Ciel since they "saved" him; Lau also decides to stay with Ciel. Soon, they learn that Agni and Soma are looking for Mina, and throughout the day, he joins Soma and Agni as they interrupt Ciel during his lessons at whatever available opportunity.
At fencing hour, Ciel challenges Soma to a match. During the match, Agni intervenes and unintentionally hurts Ciel's arm in the process. Lau tosses a sword to Sebastian and tells him that he should take reprisal for his master. However, after the match, Agni and Sebastian are tied, much to Lau's disappointment.
The next day, another mysterious attack occurs, and Lau points out that Soma and Agni have been suspicious from the start. They decide to wait until nighttime to investigate Soma and Agni who usually leave every night. Lau, Ciel, and Sebastian then follow them, and they discover that they are simply looking for Mina.
Later, however, Agni leaves on his own; Lau, Ciel, Sebastian, and Soma follow him as they are all unaware of his motive in going out arbitrarily at night. They eventually end up at Harold West Jeb's house, who is an importer of trade goods, and Lau notes that they are in the same business. They sneak onto his property with Sebastian lifting Ciel over the wall while Lau and Soma are forced to climb over. Lau soon calls them over to the entrance, as he has already knocked out the guard personnel by rendering them asleep with a needle soaked with a drug- an ancient Chinese technique. When they respond in a disapproving manner, he nonchalantly states that at least the guards are not dead.
They go inside and eavesdrop on Harold and Agni. Later, when Soma bursts in, he watches the ensuing fight. Lau and Ciel deduce that Harold is involved in the black market, so Lau concludes that this matter is in Ciel's jurisdiction. Sebastian rescues Soma while wearing a stuffed deer's head, which amuses Lau. When Lau deems it too dangerous to remain there, he carries Ciel out and back to the townhouse. There, they speculate that Agni betrayed Soma in order to earn Harold the Royal Warrant, and in return, Harold would release Mina.
Ciel decides to obtain the Royal Warrant for the Funtom Corporation, and Lau agrees, saying that launching into food industry will also deter competitors. However, Soma announces that Agni's "Right Hand of God" will be unbeatable and claims he has never tasted a more delicious curry than Agni's; Lau and Ciel derive that his nickname is not conceived in respect to his strength, but rather because of his god-like capability in preparing curry.
Later, as directed by Ciel, Lau uses his position as the head of a trading company to obtain the best spices in a short period of time and complains that he had to prepare them all in one day despite not being an expert in spices. Ciel counters that only on occasions such as this is Lau beneficial and Lau concedes that it is never a bad time to do Ciel a favor. He then also aids in taste-testing the curry until Sebastian can make a competition-worthy one.
Lau follows Ciel to the kitchen, where Ciel requests that Sebastian prepare him a chocolate cake for a dessert. Out in the hall, Lau comments that the inconvenience Ciel has imposed on Sebastian seems to indicate that he would like Sebastian to lose. Ciel says it would be more interesting than obtaining the Royal Warrant if he did, and Lau calls him a bully.
At the competition, Lau arrives with Ran-Mao, and he introduces her as his sister although they are not related biologically. They speculate the possibility of the disclosure of Harold's dishonest deeds by Agni should he be released. Lau then asks if Ciel would kill Agni if he was Harold, and the latter finds it excessive. Lau casually states that if it was him, he would do as such, and he adds that he is intrigued by Sebastian's strategy in the curry contest.
After the competition is declared a tie between Agni and Sebastian, the Queen arrives to cast her own vote. When reminded of her dead husband, she breaks down crying; Lau comments that she seems like a complex character, and Ciel admonishes him. After she has recovered, she officially announces Sebastian as the winner. Seeing Harold's distress upon losing, Lau follows him and Mina to an alleyway. He remarks that while Ciel would let them go, he must discipline the "naughty little mice" that made a mess out of the East End. Hence, he keeps a "cat", referring to Ran-Mao, who violently swings her clubs. They scream, promising to never repeat the offense.
Phantomhive Manor Murders Arc
Lau and Ran-Mao are invited to a party thrown by Ciel. There, he introduces himself to Arthur Conan Doyle, and tells him that though Ciel is moody, something interesting is bound to happen. When Ciel introduces the other guests to Lau, Patrick Phelps is shocked to hear that Lau manages the Kong-Rong Company, but he goes silent when Lau glares at him. When Ran-Mao flirts with Georg von Siemens, Lau attributes her bold action to her supposedly pampered nature. He and the other guests are impressed by Grimsby Keane and Irene Diaz.
In the midst of the festivities, Grimsby and the other guests hear a loud scream from Georg. They rush to his bedroom; inside, they discover, to their unanimous horror, that Georg has been killed. After Baldroy and Finnian move Georg's body to the cellar, Lau points out that the storm will keep the Scotland Yard away and that they are probably trapped in the Phantomhive Manor with the murderer. They contemplate about the details of the murder, and Lau suggests that Georg's death is a locked room murder. When Karl Woodley and Grimsby start fighting, he easily stops them and asks everyone for their alibis. When it is his turn, he says that he and Ran-Mao were drinking in the lounge with Karl. Ciel does not have an alibi, and Lau relays his suspicions about Ciel. He then proposes that they confine Ciel for the time being, to ease everyone's anxiety. However, he refuses to be the one to watch over Ciel; to make sure he does not escape he nominates Arthur instead. Afterward, Lau and the other guests are escorted to their respective rooms.
The next morning, Lau and the other guests discover the brutal murder of Sebastian Michaelis. Lau notes that it must have been impossible for the confined Ciel to have committed the murder, and he adds that things "just got interesting"; Arthur, who is beside him, is shocked by Lau's sinister smile. Soon after, the guests examine Sebastian's body. When Lau comments about the savagery of the murder, Finnian emotionally demands that they stop, as they are discussing the appalling details in front of Ciel. They decide to move Sebastian's body to the cellar for the meanwhile and plan to pursue the topic at breakfast.
Later, at the breakfast table, they realize that Patrick is absent. They head to Ciel's bedroom, where Patrick was assigned to stay in. When they find that the door is locked, Grey swiftly cuts it down, to Lau's amazement. They hurry inside, and discover Patrick's corpse. While everyone else is concentrating on Patrick, Lau and Ran-Mao rummage through Ciel's wardrobe, much to Ciel's annoyance. Soon after, they have dessert in the drawing room where they discuss the three murders. Ciel voices his suspicions about Lau, which are derived from the facts that Patrick was Lau's business rival and that Lau carries around a large needle that could have inflicted the wound they saw on Patrick. When Lau displays his needle, Karl and Grimsby rashly jump to the conclusion that Lau is the murderer. Lau explains why he cannot be the murderer and wonders aloud if Ciel is taking revenge on him; Ciel assures him that he is simply teasing him for suggesting his confinement earlier. When Karl goes berserk at the idea that there is most likely more than one murderer, Tanaka effortlessly suppresses him with a move Lau recognizes as Japan's "baritsu."
Ultimately, the group allows for Arthur to dictate their actions from here on out, as through deductive reasoning, he is the only one who could not have committed any of the crimes. They decide to investigate Sebastian's body in the cellar, but Lau asks to stay behind to enjoy tea with Ran-Mao. Subsequently, Arthur explains to all the guests that their rooms and belongings must be checked, and they give their consent; Lau is the last room Ciel and Arthur inspect for the male side, and just like the other rooms, they do not find Sebastian's key. The group gathers in the drawing room once again, and Lau hypothesizes that the key could have been thrown outside; this prompts Finnian and Mey-Rin to volunteer to search outside. Afterward, Lau suggests the idea that there is a thirteenth person in the manor, and that he is probably waiting for the right moment to strike.
Soon after, Jeremy Rathbone, the "thirteenth person," is brought to them, much to their astonishment. Lau claims that even he did not expect for the thirteenth person to show up so soon, but he then demonstrates that he does not have a clue to who the thirteenth person is. After they verify that Jeremy is not involved in the murders, Jeremy is allowed to lead the investigation.
For dinner, the group eats the scrumptious steak meat the Phantomhive servants have prepared. Lau presses for the truth behind the incidents, but Jeremy advises them to not be hasty.
While Jeremy implements a plan to catch Patrick's killer, Lau and the rest of the party members accumulate in Karl's room and wait. After a while, Patrick's killer is revealed to be an African snake that has been trained to attack whoever or whichever harbors Ciel's scent. Lau says that if Ciel had died, he and Ran-Mao would have been in trouble. They soon deduce that the snake must have been smuggled, which brings their attention to Karl, who specializes in the African diamond trade. Karl tries to put the blame on Lau, but Lau rebuts the accusation by stating that Kunlun does not do business with African companies. Jeremy has enough evidence to pin the murders of Georg and Sebastian on Karl. After Karl is detained, Lau joins in on the toast to celebrate the solving of the case. He and the other guests later safely leave Ciel's manor.
Luxury Liner Arc
One morning, Lau and Ran-Mao barge into Phantomhive Manor, startling Ciel Phantomhive. Lau expresses his disappointment that Ciel has already finished his breakfast, for he was planning to eat it. He offhandedly notes that he thought Sebastian Michaelis had died recently, and Ciel scolds him for not listening.
After he is seated and given food, Lau reveals that he has come to discuss the Karnstein Hospital, which reportedly revives the dead, as claimed in the newspaper. He informs Ciel that the hospital has been doing a lot of shopping in the back docks he is in charge of. The hospital often illegally shops for foreign slaves, but the amount has increased abnormally as of late. He voices his doubt that a hospital could fit so many people, and he comments that it is disastrous for such an underhanded hospital to feature in the regular society's news. With this information, they speculate that the hospital is conducting illegal human experimentation, and Ciel orders Sebastian to investigate. Afterward, Lau and Ran-Mao take their leave.
Public School Arc
Sebastian Michaelis asks Lau and Ran-Mao to attend Weston College's annual cricket tournament, along with Lau's collection of women, so that said women can distract the other cricket players for Ciel Phantomhive's sake. Lau agrees and brings them with him on June 4, the day of the tournament. There, Ran-Mao holds up a betting board while Lau attempts to persuade other spectators of the tournament to place bets on whether Red House or Blue House will win the match.
Later, Lau, with Ran-Mao sitting in his lap during Ciel's final match with Green House, is flanked by several other women. Upon seeing the women display their bare legs, the Green House players become flustered, as planned. After a certain informer reports them to the officials, Lau and his women are forcibly taken away from the venue. Despite this, they are later able to witness Ciel's victory and the birth of the second "Miracle of Sapphires."
Blue Memory Arc
After Scotland Yard places a bounty on Ciel Phantomhive for the Sphere Music Hall serial murders, Lau and Ran-Mao intercept Ciel, Sebastian Michaelis, and the other members of the Phantomhive household, bar Tanaka, in the sewers below Pitt's Lark Photographic Studio. Sebastian asks Lau if he is cooperating with Scotland Yard for money, to which Lau replies that he would cooperate with anyone for money. Lau orders Ran-Mao to hunt, and she approaches Baldroy and offers to treat him. The Phantomhive household is then escorted to one of Lau's opium dens.
Snake is nauseated by the smell of opium, and Lau says that such provides his customers with "sweet dreams." Lau orders his female attendants to accommodate the Phantomhive household with a bath, a change of clothing, and a meal.
Later, the Phantomhive household, dressed in Chinese clothing, is served a luxurious meal consisting of Chinese dishes. Lau tells Sebastian to drop the formalities as he is not assisting Ciel for free; Ciel must handsomely recompense him in the future. Sebastian explains their circumstances and reveals that they may head to Diedrich in Germany. While being fed by Ran-Mao, Lau suggests that they venture to India or China, where they are not known. He ignores Mey-Rin's comment that they are not traveling for pleasure, stating that Soma Asman Kadar may provide for them in India and that he will provide them with work at his enterprise should they choose China. He urges them to start a new life, given that, with their skills, they can survive virtually anywhere.
Ciel responds by stuffing himself with food and declaring himself the rightful Watchdog and Earl of Phantomhive and that he will fight "Ciel" to reclaim what belongs to him. Lau applauds him, stating that this earl is whom he has partnered with for business. 
Blue Revenge Arc
Afterward, Lau assigns them work at the opium den. He is impressed with Sebastian's performance, but disappointed with Ciel's performance and his refusal to wear women's clothing. When Ciel says that he will not stay in the "cave" forever and Sebastian agrees that the den is unsuitable for an earl, Lau admits that he would also like for Ciel to regain his title, or else his business might suffer. They settle in the private meeting room to discuss the situation.
Lau reads the newspapers, which vilify Ciel, and suggests that Ciel infiltrate the manor and kill "Ciel". Ciel disapproves, arguing that the formidable Undertaker is guarding "Ciel". He determines that he first must eliminate "Ciel"'s alternative sources of blood and orders Lau and Sebastian to gather information. When Lau says "Yes, my Lord" alongside Sebastian, both Ciel and Sebastian are surprised. Lau confesses that he has always wanted to say it at least once, and Ciel berates him.
Later, Lau and Sebastian report their abundant findings to Ciel, but not a single one provides conclusive evidence. When Lau mentions Karnstein Hospital, Ciel recalls the Aurora Society and has Sebastian comb through the information collected and flag anything in which Aurora Society members play key roles. Afterward, Sebastian presents his findings, having flagged four locations. The group is divided into pairs: Lau and Baldroy must investigate the former servicemen's sanatorium and dismantle any operations that harvest blood.
During their meeting, Lau, Ciel, and Sebastian determine that they must immediately leave the opium den in the Limehouse District—as well as London in general—since Arthur is aware of the ties between Ciel and Lau; and that the most discreet method of escape would be via boat on the River Thames, after which they would travel by train.
Lau has Ciel, Sebastian, Baldroy, Finnian, Mey-Rin, and Snake wear hair ornaments before they, along with Ran-Mao, leave. While the group is journeying by boat, they are accosted by the Scotland Yard's Thames Division, which monitors the River Thames. The officers demand to see Lau and Ran-Mao's cargo, as part of their London-wide investigation for Ciel. Lau informs them that he is delivering "flowers," or girls, to his clients, and bribes them. Afterward, the officers allow them to pass. Sebastian is surprised at the effectiveness of the hair ornaments, and Lau tells him that the Thames Division is independent and therefore not so closely watched by Arthur; hence, he and the Thames Division have formed a friendly relationship.
At the Reading Railway Station, the group divides. Lau and Baldroy board a train together. When Baldroy takes out a tin box, Lau assumes that their adversary must be formidable for Baldroy to resort to "that." Baldroy explains that the box merely contains candies that Ciel has given him, and Lau asks for one. Lau points out that Baldroy seems glum, and the latter comments on the bleakness of a sanatorium for ex-servicemen, as it is functionally a warehouse where soldiers, now considered useless by society, are waiting for their deaths.
Lau and Baldroy reach the Athena Sanatorium for Former Servicemen in Wiltshire. Lau reviews their roles: Baldroy is Burgh, the second son of an aristocrat who returned home after being wounded in battle; Lau is his private physician who has been hired to care for him, for he, traumatized from battle, is emotionally unstable. Their documents and identity papers have been forged, as well.
Lau and Baldroy enter the sanatorium. After Lau introduces "Burgh" and himself, a nurse leads them into a private room before stating that the chief nurse will be there momentarily. Lau is eager to meet the so-called "Miracle Healer," and Baldroy remarks, to Lau's bemusement, on how all nurses are angels to military personnel, since they endure plenty of hardships with fortitude.
The door bursts open, and a team of individuals in gas masks storms in, to Lau's and Baldroy's shock.
Lau and Baldroy prepare to engage in combat with the team. However, the team, much to their surprise, hoses them down in bleach, strips off their clothes, and proceeds to disinfect, sterilize, sanitize, and dress them in patient gowns.
One of the members is revealed to be Ada, the chief nurse, who states that pathogens are not allowed in the sanatorium and therefore Baldroy and Lau must be cleansed. Lau asks if she is the so-called "Miracle Healer." While donning a mask, she avers that the patients in the sanatorium are able to recover due to treatment involving rigorous hygiene control, which is not a miracle. The other members concur with her point, declaring that they ensure bacteria does not get into the sanatorium. Ada adds that such is the "core" of the sanatorium.
Ronald tells Baldroy that they should work together on his recovery and questions who Lau is. Lau introduces himself as Chang, the private physician for the Burgh family, and explains that he has been using Eastern medicine to treat Baldroy. Ada orders Lau to leave, since he is an outside physician, and Lau excuses himself.
Lau's departure prompts Baldroy to feign a breakdown. Lau hugs and comforts Baldroy, assuring him that he is not alone. Ronald defers to Ada on what to do, given Baldroy's serious condition. Ada agrees to Lau staying with Baldroy, even though such a stay is against the rules, stating that it is important for both Baldroy's body and heart to be cleansed for his recuperation. In private, Lau thanks Baldroy for his "great acting," claiming that he has had no countermeasure prepared when he left the room, to Baldroy's exasperation.
Ada and Ronald escort Lau and Baldroy to their ward. Baldroy notes the cleanliness of the area, commenting that there are no rats or flies. Ada reveals that the sanatorium was built according to Florence Nightingale's innovative design. Ronald avers that anyone staying in the sanatorium can return to society, even if they have been told that they will die soon.
At night, Lau rents a room in the staff dormitory. The next morning, Ada instructs Lau, Baldroy, and the others to gather in the courtyard, and constrains them to perform "healthy, vigorous calisthenics," which are a series of exercises. After the session, Ada tells Baldroy that she will show him around the facilities after his meal, and Lau volunteers to tag along. Lau and Baldroy conclude that the tour will be a golden opportunity to search for a blood-collecting facility.
After the meal, Ada and Ronald lead Lau and Baldroy to the rehabilitation room. Layla, seated on the back of a patient, is taunting said patient in order to motivate him. She then greets Baldroy sunnily and offers to train him. Ronald explains that Layla forces patients to train to the limit, albeit harshly, and Lau comments that she is "playing a different script."
Next, Ada and Ronald lead Lau and Baldroy to the operation theatre. Afterward, Ada and Ronald lead Lau and Baldroy outside toward a cylindrical building. They enter the building and ascend the stairs. Ada reveals that the last facility is the blood-drawing room.
- (To Ciel Phantomhive) "— And thus, do you become further mired in mud. Even if you reach a place from whence you cannot return, you will never utter an unsightly scream or beg for help in front of anybody. You proud hound of the Queen. I shall be careful myself to avoid falling into my lord's 'care'."
- (To Ciel Phantomhive) "I am still interested in this country. And in you as well, my lord. I expect you will continue to amuse me."
- (To Harold West Jeb and Mina) "Lord Earl said to leave the small fry alone, but those who try something once will try it again and again. He's still too soft when it comes to that sort of thing, I guess. Well, I do find his boyish side rather lovable. But I must strike some fear into the hearts of the naughty little mice who made a mess of my garden here, in the East End. That's why I keep this cat. Meow!"
- "The spider's web has already been woven. The more you struggle, the harder it becomes to escape from those bonds. Whatever the prey, once they get involved with me, catching them is only a matter of time."
- "In this world, Earl, there're people who can't survive because of the cruelty of reality. I sell those people's dreams."
- "In this whole world, everything is the dream of a butterfly."
- "One night, Zhuang Zhou dreamt he was a butterfly. He was a happily fluttering butterfly. It was so much fun. He could fly wherever he wanted. And he had no thought of being Zhou, but suddenly he woke up, and was startled to find that he was now Zhou. He couldn't decide: Was he Zhou who'd dreamt he was a butterfly or a butterfly now dreaming he was Zhou? Between being Zhou and a butterfly, surely there must be some distinction. This is what we call the transformation of things."
- Before his mission to Athena Sanatorium, the only time Lau wore something different from his Chinese clothing was when he went to Aleister Chamber's party as Angelina Dalles' lover, dressed in a traditional suit.
- Lau was included in the list of possible Jack the Ripper suspects Ciel Phantomhive made because of his skill in the use of needles and familiarity with human anatomy.
Out of Universe
- According to the official Kuroshitsuji character popularity poll, Lau is the ninth most popular character in the series, with 268 votes.
- According to Yana Toboso, Lau's special feature is his "adaptability." She also states that he may be the character with the strongest nerves as he does not let himself get worked up easily.
- When planning the cover illustration for the March 2009 issue of Monthly GFantasy, Toboso and her editor Mr. K came to the conclusion that Lau most likely does not know Sebastian's name as he generally ignores the servants and has no interest in Sebastian. Because of that, Toboso and Mr. K ultimately chose to include Ciel on the cover as a "buffer."
- According to Toboso and Mr. K, Lau is the character who underwent the biggest development during the early stages of the series, because, at first, he did not have much of a personality. However, this changed after Koji Yusa started voicing him. Without him, Lau would not be like he is now, and he would not have become an important character in the series.
|Alexis Leon Midford • Francis Midford|
|Ciel Phantomhive • Charles Grey • Cloudia Phantomhive • Rachel Phantomhive • Vincent Phantomhive|
|Angelina Dalles • Burnett • Chris Heathfield • Diedrich • Kelvin|
|"Ciel Phantomhive" • Edward Midford • Elizabeth Midford|
|Charles Phipps • Lau • Undertaker|