She, an ordinary female student, accidentally traveled to the world of vampire knights because she filled out a volunteer form. However, who can tell her why she shrunk into a child like Conan after taking APTX-4869? The triangular relationship between Yu Ji, Ling, and Jiu Lanshu was complicated and confusing, and she didn't want to get involved. Although they were just friends, she was deeply attracted by the blond boy's smile that was as warm as the sun. Obviously they just want to treat him as a family member, but they unconsciously have a vague feeling towards him who is as cold as ice. Unknowingly, she was also involved in the whirlpool of the plot. Should they follow the development of the original plot, or change their fate? The answer is not yet clear. If we can stay together, we will never be apart. I would like to accompany you to watch the flowers bloom and fall, and to watch the clouds roll and relax. The ending HE is divided into two routes.