Rainbow Dash has recently moved to Canterlot to get a new job as a chemist. She now lives in a crappy, crowded apartment with a minimum wage job while Tank has to stay with Rarity, due to the apartment's policy. As you can see, Rainbow was angry. Very angry. One day, when Scootaloo comes over and confesses her love, they get in a fight. In a fury, Rainbow kills the younger mare. After Twilight convinces the other princesses that Dashie didn't mean to kill Scoots, it's up to her and Rarity to help Rainbow get over the guilt and grief.
Warning, Contains: [spoiler]Violence, RariDash shipping, Anthro ponies, a little bit of ScootaDash shipping[/spoiler]