♂ m

The protagonist, who accidentally finds himself teaching a class for pregnant women.

♀ f

Single mother. Attends Kei's class.

♀ f

Married woman, and a student in Kei's class. Target of Kei's desires when the story begins. She's an airhead and she believes Kei's lies about sex.

♀ f

Kei's childhood friend.

♀ f

The protagonist's sister. Married, but living at home for the end of her pregnancy.

♀ f

Kei's and Momo's mother.