
Think of it this way: The reason why Kang Moo will always choose Kirin is because Kirin restrains him. Example: its like a person who is born to like to smoking. He knows he shouldn't smoke because it harms his health but he can't help smoking. So Kirin is like his fake nicotine: it is not as nice as smoking, but it works well enough. This fake nicotine is very important to his survival and he needs to keep that it (aka Kirin) happy and alive by his side. It is obsessive, possessive and over protectiveness. But the closest kind of "love" Kang Moo can feel (remember psychos can’t feel love, they lack empathy)
This is the Author’s comment on the relationship: “The reason Kirin is with Kangmu is because it is oalready a community of fate. Both Kangmu and Kirin are the only and necessary beings of each other. Of course, Kirin loves Kangmu and that is one of the reasons. It can be said that the reason for being a common destiny is bigger than feelings”
Onestly I loved it, it think I'm gonna re-read it again but I have a critique, I mean I think the seme is more a sociopath because he can love, if the was a psychopath the realtionship would have ended a long time but they didn't, I think he a has various disturbs but definitely not a psychopath because if he was this story would be definitely impossible.