>>279725941
The goldfish that show up at the window each night to take him to the park, where he was told to perform a certain ritual each night in front of a shrine, in order to open the gate.

Ukitake's theme is the goldfish
The beginning of hell arc starts with Ukitake sharing a story of his childhood about goldfish
The name of his shikai
Ukitake has always had some "twin goldfish" theme to his character