In general when an animal shows you their belly, they are allowing themselves to be vulnerable. This holds true for cats. The abdomen is the least protected area of any mammal and thus the most protected from danger when threatened.
So when a cat shows you their stomach they have just announced that they feel safe in your presence. Its like a billboard sign saying, “hey I trust you”, you’ve been accepted into your cat’s realm.
This abdominal exposure is NOT and invitation for belly rubs! You may have the odd cat that enjoys them but in general – when a cat shows you their stomach, no matter how drawn-in to execute a belly rub, DO NOT DO IT; danger may ensue.
That is exactly what my cat does. She comes over, does some head butts to my hand as I type, shows me her rear a few times then drops and rolls. Because I live with and love dogs as well, I find myself forgetting that she is speaking cat and go to rub her belly. She will then curl in a ball, use all four paws against my hand and pivot off, leaping away like I just violated her – which according to cat code, I did.
So heed caution when a cat shows you their belly. Admire it from a distance – a safe distance. For those that enjoy the touch, be careful – that enjoyment can change to distaste in a matter of seconds.
Don’t let your silly human instincts override what you now know to be cat communication. Be honored to be given sight of the belly but pretend you are at a museum – no touching. Go find the dog, he’s been begging for them for hours!