I thought one of the twists was going to be that the girlfriend didn't exist and dark-haired girl made her up to get bully-girl to make a move on her. The ending of the story doesn't necessary contradicts this interpretation, but I wish the girlfriend and boyfriend would have been even a little prominent because they barely matter in the story and that takes away much the fun out of the cheating tag.
Still the sex was hot and the relationship it's twisted enough so I'm saving this story.
