Hi Lexi,
Cats and kittens are individuals like people are. While some kittens are very friendly right away, it takes time for others. People have to realize this that don’t have cats. You don’t (not if you are smart anyway…) approach a dog that you don’t know and try to pet it. Cats are the same way. There are all types of body language that a cat gives (which you mention in your title) that is a clear indicator that she doesn’t want strangers to pet her. Growling and hissing, ears laid back, tail switching back and forth are a few that she is uncomfortable and feeling threatened. Let her approach the newcomer, if she feels comfortable she will sniff them, but they shouldn’t make any sudden moves to pet her when she does or they could get scratched or bit. She might come around, or she may be one that prefers *her people* and no one else.
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