I had a friend in high school whose cat was really into feet. I slept over her place once, and must have been warm because my feet ended up exposed. I woke up to see her cat enthusiastically licking my toes. I gasped, "Fluffy!" [not the cat's real name]. He looked up with what looked like the cat version of being totally caught in the act, and just stared at me for a second, then turned and ran away.