Tachibana Kasumi

She is the only daughter of a wealthy family. She is soft-spoken, chaste, and a bit of a Yamato Nadeshiko, but her appearance is somewhat gloomy. She is weak to pushing and not very good at asserting herself. She is also somewhat indecisive.

She has been friends with Mizuru since they were both in an all-girls' school. She got married and gave birth to a daughter right after graduating from an all-girls' school, but left her husband soon after that.

She has had no experience with men since then, and was feeling physically inadequate when, at Mizuru's urging, she and Shunji entered into a sugar mommy relationship.

At first she was hesitant, but as she got used to it, she began to ask him out on her own. She is often passive when it comes to sex, but once the heat is on, she becomes bold.

"It's because of Shunji, that my body has become so naughty!"