Board Thread:Theories and Speculation/@comment-26369387-20150823132608/@comment-734582-20150830131430

Shock Dragoon wrote: I can't imagine Kishi would go this far just to end right before the "zen" which is last.

I figure this will either be a databook that covers another canon movie, the last volumes, or the big daddy data book revealing ALL secrets of the series. I head rumors that he had a lot of Ootsutsuki backstory that he decided not to put in Naruto. It may contain that. Considering he's gonna launch a non-naruto manga, he may preserve Shen in case he needs money later.