Manga where the seme is good at cheating when he's playing cards or random games and the u...

Manga where the seme is good at cheating when he's playing cards or random games and the uke is gay and he's in love with the seme, then he (the seme) found out that the uke is gay.

Btw, I think the uke has a friend who's also gay and he promised him something when they were kids.