The main character, Yuzuki, is a very ordinary girl. If there's anything different from others, that is her vampire childhood friend. Since she gave blood to him as a child, Yuzuki has been regularly donating blood to the vampire, Akatsuki. As the days went by, the two became adults. It was always a friendly relationship between Yuzuki & Akatsuki, but since she got a job, his strange words and behaviors have gradually increased ... The appearance of Akatsuki became strange when Yuzuki got a job and started living in a new environment. After learning about the existence of a male employee who accompanies Yuzuki, Akatsuki advises her to be careful. However, Yuzuki, who is dull in her love of color, lightly treats the advice of Akatsuki. After that, Akatsuki gradually began to bind her Yuzuki. And after an incident at her company drinking party, her patience for Akatsuki finally reached its limit. Akatsuki who forcibly robs of Yuzuki's lips, muttering, "If someone else steals it ...". At the same time, Yuzuki's consciousness goes away, and when she wakes up next time, all her clothes are taken off ...