The Obsessive Male Leads Wants to Eat Me

Summary

I possessed someone, an extra, in a depraved adult BL novel and met the young obsessive male lead (top).
After being bullied by the bottom for years, he turned to a darker path in his adulthood and became the crown prince, indulging in imprisonment, obsession and all sorts of heinous adult past-times.
Hmm… Then, if the bottom never bullied the top, it would have a happy ending, right?