Gakuen Shinshoku: XX of the Dead

And so those strange creatures took the world by storm. Humans are being hunted and turned into zombies or used as hosts for parasitic tentacle organisms. As the global epidemic throws the world into panic, Houichi, his close friends, and teachers barricade themselves inside the school. However, the creatures gradually make their way into the campus and start attacking the survivors. Those who are attacked surrender themselves to pleasure and begin to turn…