[Synopsis] Miyu Hijima is a quiet, modest girl with big breasts who serves as a library committee member. Then, it's her turn to be the toilet girl. The toilet girl duty is a ridiculous rule that requires the female students to take turns satisfying the sexual needs of the hot-blooded male students. Having never even seen a penis before, she becomes increasingly addicted to pleasure through her erotic experiences... This is the first time that Miharu Usaki has appeared in a collaborative work, and she has recreated this hugely popular CG collection in its entirety!