Responses
I wanna know
http://www.mangago.me/read-manga/kimi_towa_gokai_kara_hajimarimashitaga/ Wait hold up could it be this one? It’s kinda similar
http://www.mangago.me/read-manga/that_summer_kim_hyun/
This one is quite close to your description
I’m pretty sure this is a BL but I forgot the name of it. I’m pretty sure one guy is really popular and the other is just their friend and he delivers love letters to his friend that girls were to afraid to give to him. But the popular one is in love with the friend so he thinks that the love letter is from his friend, but then realizes it’s not but that scene was cute and I forgot the name of the BL