I think post pandemic readers on here just lack media literacy. I see the most abysmal arguments that just scream this person doesn't want to use they head. The green/red flag bs is the worst thing that ever happened to the bl fandom. These characters are created to emulate humans yet readers want them to have the emotional range of fish. People seriously want character devt and progression in 10 chapters then start yapping how the writing is shit when they are the ones who don't have the patience nor perseverance to stick with the story and see how it unfolds.
That's what I also see. It's scary to think about how much I liked Sekaiichi Hatsukoi 6 years ago despite the abuse Ritsu had to endure... I think it was also about me relating to the characters' pain and conflict.
It's especially sad because you can see this all over the world. I started watching Columbo a week ago, and I was gasping from how realistic the portray of both sides were. Nowadays, people romanticize shallowness, abuse and power, it's a tragic thing to see...
As much as I sympathised and empathised with Cain I can never call him a green flag. On surface level his actions seem very harmless but they were problematic and general aided in reducing Jooins quality of life.
1. He lied and tricked his way into Jooins life. He carefully curates a whole persona that is dedicated to only chasing after Jooin. The person he is with Jooin and the person he is with his family are two separate people. Jooin never even gets the chance to know who the real Cain actually was.You can say that it's normal and people do it all the time but in this context it isn't because even Jooin picks up on it and when he asks Cain to bear himself he doesn't. He is given a chance to be the one and doesn't take it because at that point he had already started to feel guilty for overstaying his place in jooins life. When you lie about who you really are you are denying the other person the opportunity to love the real you.
2. Cain constantly infantalises Jooin. He may not have done it intentionally but he did it anyways. Throughout the series he behaves like Jooin is a literal child that needs to be protected from the big bad Yahwi. Jooin is a whole grown man who can handle his business. Cain assumes he knows what's best for Jooin without ever having that conversation with juju. By default he even underestimates Jooins feelings for Yahwi and believes he is the better option and that Jooin can only be happy with him. Let's bffr who was he to ever decide that? I would confidently argue that this narrative of "he was just trying to protect Jooin" is just bogus because Jooin never asked him to do that. In facts Jooin tells him to not pity him and not to insert himself in his Yahwi business. He went and did things on his own and believed Jooin should feel enamoured when all it did was burden Jooin.
3. Invading and basically taking over jooins personal space. I hate how people rename this as "domestic life" when even in the end Jooin doesn't have a safe space to be by himself to just unwind and be with his thoughts. Maybe is genetic considering he is British and they travelled all over the world feeling entitled to people's places and property. And he does this intentionally to keep Yahwi away cz he knows Jooin would never bring Yahwi over while he is there. This also trickles down to how he basically obstructs Jooins study time in his own place when he had already finished his coursework and was just waiting to graduate while Jooin still had several years in school. You'd thinks he'd be sensitive enough to at least think of Jooins studies but nooooo he is protecting Jooin from basically nothing. Maybe he thought Jooin would drop his studies to travel with him or something. All this just circles back to how he believed he knew best.
4. His general "obliviousness" to the fact that he was also a contributor to a shitty situation isn't green flag material. Cain stood to benefit the most from Jooins confusion and I personally think he was betting on jooin to pick him before having any clarity that way Jooin would feel too guilty to leave him afterwards. Throughout the series he uses the fact that Jooin pities him to guilt trip Jooin into letting him stay in his life. The entire time he knew Jooin didn't love him and just felt guilty and he was okay with that situation instead of removing himself and letting Jooin pursue his true happiness. To him Jooin pursuing love with Yahwi may not have made sense but it was never his place to decide for Jooin what his happiness should look like.I personally believe up until the end he was okay with a miserable Jooin with him than a happy Jooin with Yahwi.