someone who's constantly tagging photos of their friends on facebook. usually also taking a lot of photos and posting them on facebook, followed by tagging their friends in them.
derived from combining drag queen, with tagging, with calling someone the queen of something, if they do that something a lot.
to tag someone in a photo on facebook is to link their face in the photo to their facebook profile.
oh man, he's such a tag queen.
she's a total tag queen.