Cat behavior is something very difficult to understand for beginners and when you see cats sitting like humans or do similar other random things, you might get as much confused as cracking up instantly. Cats can do both adorable as well as annoying things that will leave you puzzled enough to wonder why in the world they would ever do that. From sitting up straight to curling up when petted, there are a lot of indications that can be made out of the sitting positions and body postures of cats.