There was obviously a group of attractive dark guys and they were in of her classes. She finds out that her mother worked for them and did sexual favors for them and her mother passing away meant the debt was passed on to her and they "owned" her now.

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There's a scene where she is chained in the main love interest's room who is a psychopath. They were all actually older than her and had lied to be in all of her classes. They are all extremely powerful and in powerful families.

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Not sure but sound like a good book!

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