Euh, maybe because the manhwa LITERALLY shows Ra-im using the fact that Eunhyeok believed she was his half-sister to guilt-trip him with the promise he made to her dying mother to take care of her? He genuinely believed he was responsible for her because of his father’s actions. She knew that and used his guilt to keep him around. You can criticize him for staying in contact with her, but acting like he had no reason to do so means you either ignored the context or conveniently forgot it. LMAOOO

No but wtf was eunhyuk thinking keeping in touch with raim. Sooae is right he's insane. This is insanity.