After the incident in her first year, Seki Yumiko started to close her heart from others. Until finally in her last year of high school, she never thought that her life would change because of one person.
A rather self-proclaimed perfect person, in her eyes she could do no wrong and no matter what everyone will come to adore the ground she steps on, if not...then, th-then...!
Before she knows it she finds herself trapped in a killing game with several high school students, whilst she knows that no one would ever have the heart to kill the very embodiment of perfection...she can't help but feel a little nervous.