hi so u might have understood the story wrong. there was so empathizing or anything hahaha... he recognized that he was a maggot in her life so he removed himself too!
He is almost seen through a tragic failed romantic lead at the end with how he couldn't get her and therefore does one final act of kindness by saving her. Also the role reversal that happens in the end too alludes to a romantic lens between them albeit toxic. It's not the relationship itself that is problematic as it can happen in reality but the author's intention to show that perspective after all that has happened. I don't see point in it other than the author trying not to make him unappealing.
i just saw it as the author portraying his view on his psychotic mental illness seeing as how he ruthlessly applied his own logic to himself (〜￣△￣)〜
It was going good until the story decided to empathise with the psychopath. The last few chapters were romanticizing him as it showed his pov