Board Thread:Episode Discussions/@comment-1251315-20160505114817/@comment-1251315-20160505115731

An Advocate for Manga wrote: He was talking about next week. The filler about Kaguya (which we all wanted 8 months ago before the Filleryomi began). Wouldn't really say that content expansion is filler either. The manga chapter does state that Black Zetsu told a story, but wasn't in detail, so the anime is simply expanding on that "story", presumably using canonical fact from other characters and a bit of own stuff to create a semi-canonical filler. But it's useful filler, not junk filler of irrelevant content that had nothing to do with forwarding the story.