Senior student Katerina “KC” Chariot is a good girl with a secret. She’s so nice she has an impossible time swearing unless she’s using pretty British cuss words. She also likes to fantasize about hot guys in her school. But it’s for work. Really. Katerina is an aspiring mangaka, and she needs “inspiration” for drawing smutty scenes. Unfortunately, one particular fantasy about the Japanese-Russian transfer student Yuki Himura gets the better of her. She ends up unconsciously moaning his name – in Yuki’s presence, too. In a twist of fate, Katerina finds herself agreeing to become Yuki’s secret toy, which sounds a lot worse than it actually is- especially in the eyes of her Theology-professor dad. The whole school thinks of Yuki as the ideal guy – gorgeous, smart, and sweet. But with Katerina, he’s the Devil sent to torment her, seduce her, and – worst of all – he’s making her fall in love with him even though he's said it’s the one thing she should never ever do.