The protagonist is a man that is locked in a school with (3 I think) girls. The girls have to find Crosses through the school, and if they find you they have to try and make you cum and you have to resist (the sex itself is kind of like a turn basaed system). If they fail to make you cum they lose a heart, and the more hearts they lose you win options like play with they nips/clit. If they run out of hearts something bad happened to the girls, and if some girl got all the crosses something bad happened to the protagonist.