Ichiki has been accepted into the super-preparatory school that his sisters attend. However, since I was accepted just in time, I feel like a dropout as soon as I enter the school. Natsumi even witnesses him masturbating hard. I thought she would despise me, but Natsumi helped me masturbate. She also says, I'll be your lover for a limited time until you get better. It seems that she's been worried about Ichiki for a long time. And when Akiho found out, she also declared that she would be a lover and the sisters would have sex with Ichiki as if they were competing with each other.