Mizuno Chihiro was unable to control his urges and got erect very easily. Because of his constant tardiness, he was sent to participate in the re-development system together with two other problematic senpai, Takatou Shinobu and Kandori Akira. Sharing a room with Takatou, Mizuno became erect when he helped Takatou (a mangaka) on his smutty works. Takatou tried his best to help Mizuno but fell in love with Mizuno along the way. However, he refused to admit his own feelings and hurts Mizuno. What should Mizuno do?