in daiba’s mouth's Questions (2)

Helloooo I’m looking for Manwha where the MC was cheated on! Can be BL, GL, NL etc

I’m trying to look for this one BL manwha but I can’t remember the name…
I’m pretty sure it’s completed, the main character looked like an anorexic twink (lol) it was a love triangle + his brother was way too obsessed with him and was very controlling of him after he came back from the military.
The MC is in love with his university friend but it turned out his university friend was in love with their blonde annoying (lol) friend? Something like that.
Can someone please help me find the name