Sweetie nips, usually the back of my legs when she wants my attention or she's begging for a treat and I'm not getting the hint by her glaring at the cabinet door. She's gentle about it thankfully, or I would be missing some serious flesh by now.
She hardly ever meows and when she does it's more like a squeak.
its probably very individual, like cats are. mine doesnt do it for attention, cus she has usually gotten a lot of attention by the time she tries to nibble my face

its often if i lay back, watching a movie, and got her on my chest, she will crawl up to my face like a worm, and nibble my chin

cats are known also to adapt their sounds, and even try out new sounds, if you react better to those.
my cat has gone through many sounds and signals to make me let her out, for example