Kyosuke never liked his step-mom and wants her out of the house after his dad died. Megumi proposes that Kyosuke can do anything he wants with her daughter, Yuna, if he allows them to stay. He allows them to stay.
Takato Keisuke and six females are locked up in a dungeon underground. According to the rules, the only way to escape from this place is to rape all six of them. One by one. Can they escape from here and go back to being normal? Or is this going to change them for the worse?