My Little Pony: Equestria Girls - Summertime Shorts S01 E16 Good Vibes

While feeling down at the Canterlot Mall, Flash Sentry sees Trixie carrying a heavy load and helps her out. His good deed starts a domino effect that spreads positive feelings to other people around the mall. That domino effect eventually loops back around when Sunset Shimmer offers Flash Sentry some sushi to cheer him up.