After Kaeya and Diluc had their fight, Kaeya ends up running away to Sumeru where he studies in the Akademiya and becomes a doctor and lives his best life their with the Sumeru characters but after a while he decides to go see how Mondstadt is doing, with the company of a few others of course. On his journey he reopens doors he once closed and reunites with others he thought he had left in the past.