What they say: Seriously, try talking sense into a cat, they just stare at you with their LIFELESS patronizing eyeballs, for like, a couple of seconds, then they just walk away! And your like, don't turn your back on me, they're like MNYAH!, then your all like, grrr, then they're all like, mnAYH! but it is what it is, i guess.
Credit to Whoever made that audio, and undertale.