The world has come to placing women above men due to females having higher physical and spiritual ability. In order to escape the oppression, most males decide to run away from the real world and indulge themselves in the 2D world.
The protagonist, besides having a sadistic mother and a masochistic father, is just a normal student. Suddenly one day, he and 7 other female students are taken to a uninhabited island in order to participate in "Sex Royale".
"Sex Royale" is a game where there are 2 teams, boy and girls, each team try to violate the other to gain points. And thus, on a deserted island, an unprecedented battle begins.
Yuma's little sister from a different father. She was conceived during her mother's NTR play. Her father gave her a picture of Yuma, telling her "If you're a good girl you'll be able to meet him some day". She grew up to be honest and sincere, just as her father told her to. Due to spending every day imagining the older brother she hadn't met, she gained a habit of delusions and passed out the minute she met the real thing, due to delusions running wild in her mind.