Can you go into a little detail about that? I've wanted to write gay or bi female lead for a while now (I have a certain voice in mind that keeps coming back to me), but like Blinkk, I'm worried that I'll somehow misrepresent or offend. Part of me thinks it doesn't matter, that I should just focus on the universal love aspect of it all and it will take care of itself, but part of me is paranoid all the same. Either way, I think it would be really useful for writers like me and Blinkk who are too paralyzed with fear to continue.
EDIT: I should clarify what I'm asking. How are queer characters misrepresented most commonly?
A common one in urban fantasy is to have them as predators. They will act in a creepy stalker way towards the same sex very straight protagonist, despite said straight protagonist making it clear there's no interest there. Bonus points if it's mixed in with also being a vampire/werewolf or something, so they keep hitting on the straight protagonist whilst wanting to drink their blood/attack them. Queer sexuality is scary!
For bisexuals specifically, they've often portrayed as extremely sexual. So they'll be sleeping with anyone and everyone. It's not that you shouldn't have characters with that sort of sex life, but for bisexual characters, that's often all that's seen. It's much rarer to see someone monogamous, for example. And if they are, there's the suggestion that they can never be happy with one partner. This is reflected in real life, where bisexuals can end up dumped by partners because it's believed it's inevitable they will cheat (usually with someone of a different sex/gender identity to the partner).
And for all genres of fiction, a queer relationship is never allowed to end happily. Someone will die/other tragedy, even in a series which is generally fluffy and the straight relationships all end happily ever after.
You best bet for realism comes in several flavours. 1) Love and relationships have the same range as straight relationships do. All that's different is the pool of people the character will consider as potential partners. 2) The personality and behaviour of queer people has the same range as straight people, so if you do things like all gay people being great at fashion, expect comments. 3) But do acknowledge societal differences, like the aforementioned problems where people assume bisexual partners will cheat, homophobia, and all that. This may not apply if your urban fantasy is very different socially to our world.