Starlight Glimmer's defeat at the hooves of Princess Twilight Sparkle and her friends leaves the mare wandering the caverns and mountains, escaping from her failure of creating the perfect society.

And yet there is somepony she cannot run away from. Somepony who keeps her awake at night, who follows her no matter where she is headed, who does not want to leave her alone despite her best efforts.

Herself.