A vampire accidentally becomes the servant of the girl who just killed him, then has to pretend to be a high school history teacher while she drags him across the globe hunting for magic artifacts. The show treats this insane premise like it's completely normal, which is exactly why it works. You're watching a comedy that knows its own absurdity and never apologizes for it, just keeps piling on the ridiculous and dares you to keep up.
When Inaho drives a stake through a vampire preying on her school, she expects to be done with the creature forever. Instead, her blood revives him, and through a supernatural contract, Mosquiton becomes bound to serve her as both bodyguard and reluctant teacher at her Catholic academy. Their arrangement is chaos incarnate: Mosquiton struggles with hunger and his new role, while Inaho drags him into increasingly ridiculous schemes to hunt for legendary O-Parts scattered across the world. Her reason is purely mercenary: sell these artifacts and become rich. With two other misfit companions in tow, the group bounces between comedic misadventures and genuine danger, constantly getting pulled into situations far stranger than they bargained for. The dynamic between the cynical, centuries-old vampire and the headstrong teenage schemer forms the heart of the show, where slapstick humor collides with genuine monster-hunting action. What starts as a simple vampire problem spirals into something far more complicated and weirdly affectionate, proving that even the unlikeliest partnerships can grow into something resembling friendship.