Kagurazaka Reika

Hitomi's older sister. She runs the brothel they live in. Lazy and worthless her only skill is selling her beauty to men for money prostituting both her sister and herself to wealthy men.

She sets up the game Kyoichi and Hime are part of but cheats through hypnosis. She wants to keep Hime and Kyoichi as servants.

Spoiler

Secretly she's been hired by Hime to help her win her brother. When Kyouichi finally shouts out 'Get pregnant!' while having sex with his sister Hime her job is done and they release the siblings.