Well, if you're going to have a villain, have the matching hero. :P Although, nothing about that avatar really suggests Dark Fairy.
Potentially a lot of Co-GMs...
Some parts of the history section might be hard to adapt to a non Fairy-tale setting, and still be plausible. xD
http://www.shomler.com/dance/swanlake/slsynopsis.html (It mostly plays out like that up until the ending.)
Creepy man kidnaps her and some other girls, and holds them hostage. (Said creepy man might have a daughter her age.) What would be the equivalent of turning into a swan during the day, and being human at night that would prevent her and the other girls from leaving this situation?
She meets a guy somewhere, they fall in love. She explains her situation, and why she can't leave...?
Creepy man learns of the guy, and gets his daughter to seduce him. (And somehow the guy has no idea he's with the wrong girl.)
Guy realizes his mistake, and somehow finds the creepy man. Fight ensues.
Creepy man kills her lover. All the girls get pissed and gang up on him, and kill him. (In Fairy Tale version, this would essentially be a flock of swans attacking one creepy man.)
Unlike that summary, the curse can be broken with Rothbart's death, and he essentially lied to her.