16-year old Pureblood Vampire Mitsuki Kobayashi is still traumatized by the events that happened 2 years ago. Her younger brother Kaito Kobayashi being murdered by Rido Kuran right in front of her eyes. After that day, the Kobayashi family went into hiding for two years. They stayed in their residence for 2 years. For these two years, Mitsuki has been having nightmares of the past events, and hallucinations of Rido appearing before her. Her parents then transfer her to Cross Academy, where her life will change completely.

A mysterious transfer student arrives at Cross Academy and Zero instantly falls in love with her, but refuses to admit it. While Kailyn tries to remember her live before the headmaster of Cross Academy adopted her. In the mist of everything that's happenings, no one expects something horrible to happen or do they?