And what do you mean, by "there is no competition."?
If no guys are around the perceived "main competition" to the love interest is eliminated. Just by the virtue that lesbians are much rarer than straight girls. Of course the amount of lesbians in yuri works is usually disproportionate to reality.
Naturally yuri revolves around lesbians first and foremost, so males do not pose any "threat" anyway, but as you can see many readers are rather paranoid and sensitive about that.
Well I like guys in yuri stories, They make the story feel real. Plus I like to see the guy lose. And, that one is as bad as it sounds. heteronormativity bores, and annoys me.
Well people are paranoid for a reason. there is just so much bad bait out there. And people will watch it in hopes of a good ending, because there is not many stories with lesbians to begin with. I used to do exactly that, but it's become too annoying for me.
I like me some genuinely good story with male (supporting & supportive) characters, too. Shame on the bad tropes.
I love Mophead in Tamen De Gushi. He's Sun Jin's best friend and instead of having an issue with her falling for a girl, he's all for it and helps her out any way he can even if it results in him being the butt end of a joke.
The great thing about his character is that it really doesn't matter that he's a male. He's her friend, and he's helping her because that's what good friends do. It feels so strange to focus on someone's gender more than their personality.
I'd probably still like the character regardless of the gender, but honestly a small part of my appreciation for him really does stem from him being a male character in a yuri story that is just straight up a best friend rather than a source of love drama. If it's strange that I appreciate that then I dunno what to tell you.