When nights grow lonely at the dorm, boys turn to naughty stuff. While pleasuring oneself is commonplace in a house full of teenage boys, Kasumi is nevertheless shocked when he catches his roommate Hiyori engrossed in self-indulgence. What’s more shocking is that Hiyori challenges Kasumi to stay and watch, that is, stay if Kasumi feels something for the older boy. Will he stay or go? Which option is more rewarding for Kasumi?