My Dad's cat Miss Kitty is that way. Most of the family is afraid to pet her but me and I have to admit I'm almost afraid sometimes. I've learned her signals but I don't always notice fast enough.

When hubby and I were dating in high school his family had a cat named Tum Tum. She had a three stroke limit and if you didn't know that and stroked her a fourth time you would draw back a bloody arm. I learned the hard way. Some cats are just that way.