Oogami Island, a tranquil green paradise, transforms into a hellscape of desire and madness when the UNKNOWN-Level 4 virus re-emerges years after its supposed containment. Infected individuals spread the contagion through violent sexual acts, creating a chain reaction of rape and depravity. Both male and female carriers assault victims, and even uninfected humans succumb to the overwhelming atmosphere of lust.

A group of survivors—including high school newspaper club member Makoto, his friends, cheerful lowerclassman Akari, upperclassman Aitsuki, and the pure-hearted cheerleaders Airi and Akari—flees into the forest toward a shrine for safety. However, the virus spreads faster than expected, and the young women's pheromones attract hordes of infected. The story follows multiple routes and focuses heavily on the violation of innocent girls whose soft, untouched skin is mercilessly ravaged.

Divided into an upper volume (Rape Harem), lower volume (Rape Party), and Route A (a world of despair and nightmares), this hentai anime adaptation of the popular PC game series delivers intense scenes of gang rape, reverse rape, mind break, and harem-style orgies. The animation vividly portrays the contrast between the girls' initial resistance and their bodies' gradual surrender to overwhelming pleasure.

Based on the erotic game by Speed.