I wanted him to suffer more

Me too. I feel like he definitely should have suffered more. He played him and just tossed him aside when he wanted. Then when he got shinobu to fall for him he goes and fucks some other dude. Shinobu would also be a dumbass to trust him again and will probably have doubts about kou because of what he's already done. You can't erase that shit. Yeah sure, they got a happy ending, but I hope people don't do this in real life. I'd rather have Kou faint and then accidentally fall of the top of some building and come to a very near death experience before I ever walked near him again, let alone love him again. Then, maybe after castrating him would I also consider being acquaintances with him.

I will forever hate these plots, because they are disgusting me. It is so not realistic. I know these people who want to somehow believe that love can completely overwrite a person. Dunno why women always harbour this arrogant idiotic fantasy and hold it over men. But it will NEVER BECOME REALITY. Not with people like this. If he cheats ones, you break up. That is it. Who the hell wants the dick (or vagina/ass) of someone, who AFTER HE TOOK YOU just went on and did others? I don't care about a past before you. If the health results are positive, have sex and be happy and loyal to each other. But if he fucks other people even though he was with you, break it off. At least for your own health and respect towards your own genitals and psychology. He will not change. A human who does this ones is prone to do it again. You might just not know, cause you ignore the sings and he/she will hide it well. I swear. So annoying.

I hate people like Kou. He's taking advantage of his partner. Shinobu was doing fine without him.. I believe time will let him meet his destiny. While Kou just needs to apologise and move on.. Let Shinobu happy with the one that will truly love him. If I were shinobu, I'll have doubts in the relationship.