Yess but not "ends up" but more like, it's thanks to the pink haired guy that Dohyun and Mogyum can't end up together even tho they actually like each other. And yes the pink haired guy have a thing for Dohyun but there's some conflicts here and there so they (Dohyun and pink boi) can't end up together.
Ahh sorry for the confusion XD yes like the reply said, the pink boi end up with Dohyun. But not really "ends up" ? There's some conflicts here and there so they can't end up together but at last Dohyun had a change of heart. Basically, thanks to the pink boi, Mogyum and Dohyun can't end up together (they like each other lmao, the ironic). And it's sad but I'm happy to see Mogyum ended up with Chamin instead--- is what I mean.
If Dohyun likes Mogyum, why does it seem like he is protecting pink haired guy? if he is, he doesn't deserve to be with Mogyum.
(I'm jumping the gun. I know. I haven't read the story. Still. I don't like the fact that he did nothing to get Mogyum out of his trauma or he is continuing to hide the whole business...chamin×Mogyum, full support here!)

kinda spoiler alert???
Be aware of the pink haired boy lmao he's the real big boss here. Pretty much a yandere dude. And yeah Mogyum's unrequited love (supposedly) also thanks to him. Kinda sad but at the same time I'm glad he ended up with the current seme instead.