Starlight did not like Sunset. She just shows up out of nowhere, she’s an alicorn and a former student of Twilight’s. Starlight was jealous. She had a severe crush on Twilight and felt Sunset was slowly replacing her. She started stalking them on excursions, showing up uninvited sometimes and trying to one-up Sunset with her magic and friendship expertise. Sunset is aware of the jealousy but isn’t into drama and Twilight is oblivious. Starlight refuses to lose Twilight, and a violent confrontation occurs.