Somewhere in the middle of butt-fuck nowhere, there’s an island with a single school on it. This single island with a single school has only a single middle schooler in it, and she happens to be a girl. Naturally, rape is involved, and this being Japan it turns out that she has a deep, unfulfilled yearning for the tiny cocks of little boys. It’s like paedophilia to the n-th degree.
And in conclusion, they raped her for the next 6+ years until she finally went to university. Well played.