"Are you saying 'Can you lend me that hard cock?" Yuma, a high school boy with a strong face but a love for all things cute, is welcomed home by Sena, a genius and beautiful boy scholar who is as cute as a doll. Yuma is thrilled to find himself suddenly living together with Sena, but to his surprise, Sena is a genius in the extreme! As he helps Sena with his research - anal development - Yuma gradually becomes attracted to him, but will he be able to escape from the "experimental equipment" that forces him to have sex as if he were masturbating...? A serious high school boy and a crazy scientist. Their encounter slowly creates a chemical reaction...