Quote from Bog Initiate
Based on how it starts (a guy looking himself in the mirror thinking he's cute and stuff), it might be Houkago Edge
. There's no school festival, though.
That's the one I was re-reading when the story came in my mind.
Sorry it's not one of those you mentioned but I appreciate it . I've also skimmed through the lists multiple times and none seems to fit the bill.
A part of me thinks that maybe my mind played tricks on me and is confusing more than one stories but another part wants to believe it's an indivudal manga.
After wracking my brain, I remembered reading the first couple of chapters of Seinen wa Ai o Kou a few months ago and it has the school festival scene, a sporty straight seme and a scene where the uke puts on lipstick. In this particular manga, the uke hated cross dressing and himself when he put makeup on.
I think this manga is where I got the idea of a cross dressing-sports festival and sporty seme.
Then I remembered reading the first chap of Kono Koi ni Mirai wa nai and in this one the MC thought of himself as beautiful when putting on make up....and he was looking in a mirror.
So prolly this is the one where I get that mirror idea from.
Then finally Houkago edge is probably the one where I got the idea of the uke thinking he'd get blackmailed the next day at school after the seme saw him.
So, this makes me believe I was mixing all these manga. (Tho I'd love if it was a real manga....maybe it is but I can't tell for sure.)
Thanks a lot @Bog Initiate for taking your time and replying. Really appreciate it