[Zen_Approach]

I think a nitty player (or even somewhat nitty players for that matter) are raising this flop with any overpair that kings beat. That pretty much narrows villains range to set/straight or semibluff with turned draw. In my somewhat limited experience these big overbet all ins on these types of boards tend to be sets.

While this could be a bluff, I tend to give players respect on these types of plays until they give me reason to think otherwise.