He's actually a psychopath he didn't see anything wrong with his action, if I remember correctly he even said, he will do it again. The thing he does regret is not communicating clearly from the start, coz luce already loved him, so if they properly communicate then there's no need to do those things.
Thanks for your answer ヾ(❀╹◡╹)ノ~ It's pretty sad that this story has totally wasted potential. If the ML had regretted his actions and tried to fix his mistakes, I could have continued reading it :( I really wish mangakas would stop making completely tyrant male leads. And if they do, at least give a revenge arc or another love interest for the main character!
Theres a revenge arc but it's only short coz the ending seems rushed. And there's no side stories. Luce actually had another love interest, but the love interest only popped out near the ending. But the side CP is really interesting, which is luce another best friend. I'm more excited about that, I just wished the author will make another story for the side CP.(≧▽≦)

The mc will beg for the ml, for his bff safety nd the ml will ask sex for exchange then he will imprisoned luce in the tower nd strip him of his position as captain of knights. He will treat luce like his wife, then they will always fight and it will end up him raping luce. Luce managed to get away tho, SUCCESSFULLY