Hello, I'm looking for any manga where the Yaoi / Yuri isn't the main subject, or even has any major part in the story, for example, If in Bleach every character was a girl, yeah it'd most likely be yuri but it still wouldn't have any affect on the story, AT ALL. You know what I mean? I just want to know if there are any manga like that at all. It seems every Yaoi / Yuri has some sort of romance...

Huh, that is a lot harder to find than I thought it would be. I just skimmed through my collection and most of the "plot-worthy" yaoi/yuri that I have are based around the relationships. Then some just don't HAVE any plot!

You may like Yami no Matsuei and Nabari no Ou (both shounen-ai ...well, I at least consider Nabari BL). For actual yaoi you could try Crimson Spell. If you are cool with slash (more plot, less focus on the gayness- but still there for those who look) then there is stuff like Aquarian Age: Orion no Shounen and D•N•Angel• that might fit.

[color=blue]THE SOUND OF THE OCEAN IS DEAD
[/color][color=gray]IT'S JUST THE ECHO OF THE BLOOD IN YOUR HEAD[/color]

hmm well for yaoi, I second Nabari no Ou. And I suggest. Kuroshitsuji ? that's the one i've thought of so far that fits your request the most, lots of subtext and at least one canonically gay character but it doesn't change the story at all. Maybe, Kyou Kara Maou and Legal Drug. Hetalia has lots of (canon?) gay but it no effects the story at all. This one isn't BL but there are many close friendships and it is a favorite of mine, Ookiku Furikabutte ; 3 ;

yuri... feel kind of dumb saying this but the first one that came to mind was Sailor Moon. Gintama isn't gay at all, but it does have an arch sort of about yuri, and the main character says it himself that they were really gay it wouldn't matter to him. Zombie Loan is one. El Cazador de la Bruja (an anime) is really good and counts I think! I just wrote whatever comes to mind, i hope at least some of my nonsense helped. 😉