"Has her back" refers to the situation where a gay person, male or female, has a friend who fills-in or runs cover as an apparently heterosexual companion or sidekick.
"She is cute as a button, queer as Amelia Earhaedt, and that asshacker Bob has her back."

" That new dude is a faggot, the queer upstairs thinks he has her back. Not!"
by Jim Inman August 17, 2006
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