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A werewolf (狼, Ōkami) is a large and ferocious supernatural being that protects the Werewolves' Forest from intruders. Werewolves are a fictitious species asserted as real and existent, for the purpose of the Emerald Witch Education Project.
Hundreds of years ago, the Emerald Witch formed a contract with a werewolf, by sacrificing her legs, in order to defend her companions from persecutors during the dreadful witch-hunts. However, her blood has thinned out much by then; werewolves now blatantly resist the conditions of the contract by attacking the villagers of Wolfsschlucht; hence, the villagers are imprisoned by werewolves, rather than guarded by them. However, if the witches execute the Ultimate Spell, thereby using a certain formula to create a source of miasma (which is like "oxygen" to the werewolves), the werewolves would be placated.
Truth Behind Werewolves
At first, it was claimed that werewolves are capable of "invoking a curse." The reality is they are just normal human males dressed in werewolf costumes equipped with gas masks; the elaborate ruse is part of the Emerald Witch Education Project — the purpose of the project is to get Sieglinde Sullivan to produce a powerful poisonous gas, which she does in the form of "SuLIN."