I'm a psych major btw and

OH MY GOD, it finally clicked for me. The reason Jaeyi has been in so many relationships that never really became serious, only for him to eventually be the one to end them, might be because he’s been trying to find the affection and validation he lacked growing up through different means. In this case, it’s through sexual relationships. He might not even consciously realize that he’s doing it, but the attention and affection from other people could temporarily fill that emotional gap he grew up with. And once that feeling starts to fade, there isn’t much left for him to hold onto, so he ends the relationship.

That also makes his feelings for Ideum make SO much more sense. Ideum is different because Jaeyi can’t just treat what he feels for him as another temporary source of affection. Like judo, Ideum becomes something he genuinely feels passionate about and can’t completely let go of, EVEN WHEN HE KEEPS TRYING TO CONVINCE HIMSELF OTHERWISE. There’s something about Ideum that makes him confront feelings he normally knows how to avoid.

And as a psych student, I feel like this also explains why Jaeyi has such a hard time communicating what he actually wants. Growing up, he was always the one expected to adjust because Jiseong was sick. Over time, that probably taught him that his own wants and feelings were less important and that he was supposed to just understand everyone else. So now, even when he knows what he feels, he struggles to actually say it because he’s so used to being neglected.

What makes it even sadder is that Jaeyi doesn’t seem incapable of love, he just learned to seek affection without having to communicate his emotional needs. Instead of saying what he feels, he turns to physical or sexual intimacy because it lets him feel wanted without having to be vulnerable.