Bizarre, unused cat people found in Super Paper Mario

Okay, this is pretty strange. All these years after Super Paper Mario launched, a bounty of unused content has been found. That includes some pretty strange looking cat people.

Here's the thing that's even stranger. These cat people only appear in unused levels in the game, and furthermore, only appear in the Korean version of the game. The Korean version came out 2 years after the Japanese release! How in the world were they left out from other versions, but included for the Korean version? So many questions...