Kuromine Chaoyang (voiced by Hanae Natsuki) is an ordinary male high school student, the only characteristic of which is that he cannot hide any secrets. Chaoyang secretly has a crush on a girl in his class named Shiragami Yezo (voiced by Serizawa Yu), but Chaoyang never expected that Shiragami Yezo's true identity is actually a vampire. If Chaoyang leaks this secret, Yezo will obviously be expelled from school, and he will never see her again. For the person he likes, can Chaoyang really keep her secret? The stubborn and serious Aizawa Nagisa (voiced by Minase Inori), the charming Shishiho Shishido (voiced by Uchida Aya), and the school's principal Akane Benmoto (voiced by Ichimichi Mao), more and more secrets surface one after another.