Naoto Watari has had his share of struggles: his parents died two years ago, and now he and his sister live at his aunt’s house. There, his desire to protect his sister earned him notoriety as “the guy with the sister complex”—which never mattered to him, as his sister always came first. But when Satsuki, a childhood friend-turned-enemy(?), becomes his school mate, Naoto’s ordinary life is thrown into chaos … and Satsuki may just be the beginning.
After breaking up with Ishihara-san, Naoto ended up alone together with his childhood friend Satsuki, and almost took her up on her offer to comfort him. Since Naoto wouldn’t have sex with her unless they are going out with each other, Satsuki told him to ask her out by the day of the school festival. On the other hand, Ishihara-san, believing that the festival’s curse will bind them together forever, is planning to get back together with Naoto. Meanwhile, Naoto is plagued with uncertainty. Who will he ultimately choose on the day of the festival?!