This is kinda different but after the sex they avoiding each other....
http://www.mangago.zone/read-manga/kiss_blue/
Sorry that I even doubt if its right!
Sorry about the vague descriptions that I gave you. It is that at the beginning, the manga does not arouse much attention. It seems to be a very common story. But soon the depth is noticeable (and I forgot the title).
About the details I remember: it seems to me that the Uke has short black hair and were introverted. About Seme, I remember that he pass me the impression of being a virile teenager , and had an athletic body.
Uke, despite being aware of their sexual orientation, was not exactly open to everyone. Only confided this to the Seme. He seemed to fear rejection by the others and feared that his secret was being exposed because the Seme was the social type and had a group of friends, as he walked through isolated at school?
As far as I read, there was no explicit sex scene, but in one of the chapters, they end up grabbing at school (on a rainy day). The first chapters seem more a monologue (memories of the past). The 3rd chapters appeared to be the thoughts of Seme, causing me the impression that the Seme, at some point, had regrets for what he did with the Uke ... and he was already an adulthood? Yes! It seems that they meet again few years later, after they start to work, but the approach was being very difficult.
A few months ago I read a yaoi manga, and I could not finish it.
I remember only that the uke noticed early he was gay because he liked the schoolmate. At first he hid but eventually confessing his feelings and eventually the Seme said something like: ". OK Let's try it." But after having one-night-stand, the Seme passes to avoid Uke ... and I do not know how the story ends ╥﹏╥