Lusamine getting de-fused from Nihilego. Before they got confirmation, the Mob actually thought they killed her.
Lillie's departure for Kanto, especially when it was revealed she was seeking out Bill. There was even a donation with an acted-out almost-love confession.
Going into Guzma's old home was a sobering experience. Nigel goes to his room, which hasn't been visited in a long, long time, he learned that his father beat him and that he ran away from home, and afterwards Nigel just spends a little while at a motel.