Grimoire of Zero—The Beastfallen half-tiger mercenary hunts down witches, but everything changes after a witch rescues him and wants him as her bodyguard. She’s Zero, who’s searching for a missing book that she’s the author of, the Grimoire of Zero, containing the secrets of Magic that could possibly end the world in the wrong hands. Since Zero promises to make Mercenary a human if he does everything that she asks, he’s convinced into helping her to retrieve the Grimoire of Zero.