Felix might be a horrible or just a serious person, but I respect him for genuinely caring about his mother. Yes, he has done some really bad things, but you can't ignore how much he cares about his mom.

She is the only who is important to him and the only one he had left after what happened to his dad. He probably appreciates how she is taking care of him all by herself and have a job at the same time.

He might be a lot of things, but you can't say he doesn't care about his mother.