The Butler, Returning Home is Chapter 126 of the Kuroshitsuji manga.
Ciel Phantomhive tells Sebastian Michaelis to inform Fred Abberline, Charles Grey, and Charles Phipps about the Bath music hall and Gregory Violet's whereabouts. They puzzle over why Blavat Sky has returned to London, despite the risk of being apprehended. When Ciel mentions Elizabeth Midford, Sebastian reveals that, during their previous encounter, she has said, "I, and only I, simply can't go back over there." He, then, states that they should return to the townhouse for the time being, and assures Ciel that he will report to Fred and continue the investigation. While he prepares the carriage, Ciel muses on Elizabeth's cryptic words.
At the townhouse, Agni tells Soma Asman Kadar that he has matured as a person during his time spent in England, and the latter agrees. Agni, then, suggests that they return to Bengal, or even visit other countries. When Soma asks him if he is worried about Ciel, he admits that he is. Soma asserts that Ciel has helped him acknowledge Agni and become more self-aware; and, yet, Ciel himself keeps trying to be alone, and refuses to accept all the love around him. He adds that while Ciel should be fine without him, he wishes to be "his Agni," to Agni's surprise. He says that he wants to be a strong man who can support someone else, just like how Agni was there for him, and declares that he is still Ciel's friend, even if Ciel does not think so. When he asks if they can stay in England a while longer, Agni, who is moved by his words, gives his consent.
A carriage arrives, and Soma goes to answer the door, while Agni makes hot tea. Agni thinks to himself that all his worry was unnecessary, and that he simply needs to protect Soma until Soma and Ciel can solidify their friendship. He discovers a partially burnt photograph of a younger Ciel at the hearth, as well as another photograph, and decides to put the remnants back together and hold onto them until Ciel is grown up. On closer inspection of the remnants, he becomes shocked.
In the meantime, Soma urges the visitor to come inside, and notices that the visitor is acting oddly. When he approaches the visitor, the visitor puts a gun to his head, and tells him not to touch them. A horrified Agni rushes over, and a shot is fired from the gun.