Наґумо Коші

Koshi is quite responsible and mature for his age. Even after being abandoned by his father, he fell into depression and tried to look for a job. When he started to work as dorm mother, even though the girls were older than him, he didn't hesitate to scold them. He even tries to warn them to be more aware of how they act and dress as he is still a boy and has desires.

On his birthday, Koshi's house burns down, and having no money, his father decides to abandon and leave. Roaming the streets, he falls exhausted from hunger. Mineru Wachi finds him and takes him to her dorm, where she gives him food. There he meets the other members in the dorm. Learning about Koshi's situation, Mineru proposes he lives there and works as dorm mother. Only Atena Saotome is against it as she can't handle being close to men. Koshi decides to turn the offer down as he doesn't want to make Atena not feel at ease at her home.

Seeing how considerate he is, Atena decides to accept him and allows him to be the dorm mother.

Koshi then starts doing daily chores, but while doing so, he often runs into the troubling members. Mineru often works with poisonous experiments and walks naked. Frey