A Cats Way Of Thinking

It's like that one thing from the True Lab in Undertale

I'll take your word for it. But you can always explain more.

In the True Pacifist route in Undertale, there's an area you need to go to called the "True Lab," where some monsters were fused together.
There, one of the Amalgamates, or fused monsters, does something similar to that

So the game's monsters have the attitude of a cat.