Makoto and Shinobu are childhood friends who Ryunosuke admires as the manliest of men. When he shares a room with them in the student dormitory, he senses the beginning of a rough but manly youth. But they turn out to be girls! And both of them!!! And thus Ryunosuke's youth becomes one of plumpness, sex, and maximum slip-up frequency!! A completely unmanly, intimate cohabitation life begins!