Although it's perfectly plausible to s*it on Kaido right now, i think it's worth letting him have the benefit of doubt. If the LN spoilers are correct, there's no NTR whatsoever.
Must admit I did not expect actual domestic abuse to be portrayed with the male mc being aggressor. Manga almost always make it be the girl that does it. Even more surprised he decided to do it in public, of all places.