Tenkousei ni Yottetakatte Shuudan Boukou

The transfer student was taken to a secret room.
They beat her. They punched her until her creamy white skin was purple. Her naked body was photographed, and her splayed sensitive genitals jammed with a foreign object. Then two men took their pleasure...

A violent, brutal mobbing of a schoolgirl.

[From DLSite English]