I wanna reread this manga but forgot the title . It was about the uke texting the 'girl' he likes, but then it turns out he texted the wrong person and they were like going out. He went with it cuz he felt guilty. The seme is actually the brother of the said girl that the uke likes
I think this is the one you're looking for
https://www.mangago.zone/read-manga/chiguha_kuna_kisu/
The uke is someone who put all his efforts to maintain his looks, but then he have a colleague (seme) who is someone who's already handsome without even trying but the seme hate socializing cuz he think its unnecessary and that it have nothing to do with his work, so whenever someone compliments him or like, someone surrounds him, he get annoyed
Lady's and gentlemen, thats how Dohyun fell for him more