Since the early death of his parents, Takami Akitoshi has lived alone with his
beautiful elder sister, Hitomi, while concealing his dirty desires for her. One
day, a mysterious girl named Mina enters his room. She introduces herself as
Death and explains that she came to take his soul because he had reached the end
of his lifespan. Hearing his screams, Hitomi runs in and, after the situation is
explained to her, asks Mina to spare him.
Mina, moved by her earnestness, tells them that if Takami fathers a child within
a week, she will let him live another 10 years. Hearing her condition, he turns
his face to Hitomi...
