Do you know why a cat rubs her checks against your leg?
She's marking you and letting others know that you are hers! This isn't the same as a cat urinating, only other animals can pick up the scent on you from the rubbing.
So what does it mean when two cats rub together?
The message is "strength in numbers, let's create a group odor."
Other Cat Clues
Tail - If the tail is straight and upright while walking around, your cat has confidence. If the tail flicks toward you, they are saying hi. If the tail is moving side to side or thumping on the floor - your cat is agitated. A light twitching means they are in relaxed alertness. And if you've ever seen a cats tail when it puffs up - they are really scared!
Eyes - Cats can't really see in the dark, but they can see better in the dark than we can.
Ears - Cats ears contain more than 40K nerve fibers, which helps them to hear very high and very low frequencies. Back off your cat, if her ears are flattened against her head, in a defensive stance or ready for a catfight. If the ears are pointed forward and slightly outward, your cat is relaxed.
Whiskers - Cats have 24 whiskers spaced in four rows on each side of hte face. Whiskers are used to protect their eyes and help side up the width of entries. If the whiskers clear the space, the entire body can get through. (This must happen after six months, my cats are always pushing their way into a empty cardboard pop holder.)
Nose - Important organ - when cats sniff another cat's scent - they learn a mini-bio - the cat's gender, whether they should interact or not, it's age and it's health status.