Board Thread:Episode Discussions/@comment-25319479-20181021102725/@comment-6036561-20181021181240

Well, it's pretty clear that "lord Ku" is Kozuchi... he even wears the same outfit as Oonoki.

Plus, Kurotsuchi looked troubled after the phone call with Naruto, and I don't think it's only for the matter of Mitsuki's "kidnapping"