One night, a succubus appears in front of the main character, but she is a rookie succubus and doesn't know anything. Also, when he touches her, her knees crumble under herself. However, she still tries to draw energy from him. He sympathizes with her and decides to give her sex lessons. His younger sister and her younger sister succubus also join them and their succubus life begins...

[From Himeya Shop]