I think, from my personal experience, that this is not just Robin's first time having feelings for a guy, but his first time having romantic feelings for anyone. It didn't seem like he ever harbored romantic feelings for his exes, who noticed it and broke things off with him. He honestly seems like someone whom a girl had confessed to and he accepted it and started dating them just because that's what he was taught to be the norm. Sure, he probably was attracted to his exes in some way, whether that was aesthetic, sexual, or sensual - but I doubt it was ever romantic.
So, having said that, having a crush for the first time ever is really confusing, especially when you're in your late teens/early adulthood when that happens. Listen, I had that experience, it took me so many, many months of confusion and partial denial to realise what was happening - and I've loved reading romance since I was a literal child, you'd assume I'd be able to tell how a crush feels like. Nope, wrong, I was so damn clueless for such a long time. I can only imagine how much harder it would be for Robin, as he doesn't seem to be the type to read romance stories like I do.
Either way, I'm hoping them all the best.
this is one brilliantly written story with everything nicely taken care of except the baby simulation part which had no closure. But that aside, its really good. But their relation is so frustrating and sad. Robin is in denial and confused coz hes never had feelings of being gay and also he only had gfs in the past. Its cruel of Hangyul to hit him with such harsh words when Robin was really concerned about him. But yes, Hangyul too has had loads of pain and heartaches for so long do we should understand his outburst too. Aagh! Hope they confess and get better from now on. Really wanna see them lovey dovey soon.
┗( T﹏T )┛