author had the opportunity to make that man suffer for the rest of his life or (in a good ...

author had the opportunity to make that man suffer for the rest of his life or (in a good ending for him) make him fall in love with another person and unlearn everything he'd done to yujun before. i guess an abuser repeating patters despite being aware that they hurt their victim (which was someone he was possessive of, but cared for deeply) is one version that can happen in real life too. but whatever