Inmu Gakuen

Based on the erotic game by Lune.

Shinji is a high school student. He loves Mayuri, his classmate. One day, a sick-room teacher, Ryoko, gives him a pendant. It seems people can have a good dream if they sleep with it. On that night, he goes to bed, holding the pendant.... A while later, when he wakes up, he finds himself being in Mayur...