Chuuya was just walking around unknown streets after getting into a fight with Akutagawa over some food, when he realized, this was Fukuzawa's territory, which meant Dazai would be around...

The chihuahua decides it's best to leave, so he goes into an alleyway that leads back to his packs territory, but has a run-in on the person he was avoiding the most... Dazai.

"Chuuya! Hi there! Long time to see! Woof!" Dazai said, running over to the tiny dog and starts sniffing him...