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.
Naoto is currently dating Ishihara-san, the girl of his dreams. On the night of the fireworks show, he was tempted to have sex with Ishihara-san. While they didn’t have sex in the end, it still resulted in awkwardness between the two later. At the same time, Makina, who had realized that she was in love with Naoto, had also been actively making advances at him. However, Naoto could only see Makina as a little sister, causing her advances to backfire…!! All the girls in Naoto’s life just keep getting bolder and bolder with their approaches! How will Naoto handle this?!