They prefer to sleep in several short spurts through a 24-hour period, rather than the single, solid chunk of sleep that most people get. This means when your cat curls up on your chest for a nap, they do it to feel safe!
Cats that headbutt or even lick you before sleeping on your neck clearly see you as a close companion. You can even see some cats show this behavior toward their canine companions, too!
You should only worry if snuggling up to your neck isn’t part of your kitty’s bedtime routine. Otherwise, it’s usually a sign that your cat feels safe and secure when you’re around!