Kayashima Aki

She is married, but because she loves hunting for men and showing off the body she's so proud of, she started working part-time at the swimming school. However, because of that she doesn't take her job seriously.

She hates losing and has a vain, child-like and prideful personality. She brags about the fact that the ability to make men look her way is her beauty secret, and thinks she's as youthful as ever. She often fights with the other married women, and aggressively seduces Taito.