A bunch of ponies summon a demon. They get a human.

A young filly doesn't like her cutie mark. She decides to do something about it.

Princess Celestia is overjoyed that her long-lost sister has returned. The castle guards? Not so much.

A story as old as time: the star-crossed lovers finding meaning in each other's embrace. But this time only one sees it that way. For the other? A means to an end.