In the Kurobara household, there are two daughters; Miki, the eldest, is serious and responsible, married and living separately from her parents. Mao, the youngest, is gentle and easygoing, working as an OL while still living at home. Their brother Kohei is a university student living alone in Tokyo. It was a rare occasion when all family members were together again after so long. Upon his return, Kohei revealed that he had gotten a tattoo and was involved in delinquent activities! Apparently, he had been rejected by a girl he liked because she found him too weak and skinny... At first, both Miki and Mao were angry and confused but decided to help their little brother regain confidence by stripping down for him...
