Usually the cat doesn't get to sleep in the bedroom, but one evening he snuck in and arranged himself on my pillow, near my head.
I could hear his purring quite loud. I like gentle sounds when I go to sleep, distant trains, planes, dogs barking, even cars. So I enjoyed listening, in the dark, to his purrs. Then slowly they faded away and all I could hear was him breathing deeply.
I'd heard him fall asleep, it was wonderful feeling.