is bleach episode 312 filler?

In the forests of Rukongai, Marechiyo wakes up from a pleasant dream. Upon realizing that he slept for much longer than he intended, he begins to run back to base.

In his eagerness to avoid Captain Suì-Fēng's wrath, he runs over the edge of a cliff and falls on top of a Hollow that is attacking a boy in a bid to retrieve an object from him. While Marechiyo is dazed by the impact, the Hollow retreats as it believes it is at a disadvantage.

The boy thanks Marechiyo for saving him and asks him who he is. Without thinking, Marechiyo tells him that he is the captain of the Second Division of the Gotei 13, but dismisses any worries as he is just one child.