She doesn’t know you well yet. You bring her food, and she likes that – so she tells you by rubbing your legs. That leaves her scent on you, so that everyone (feline) will know you are her feeder. It also says that you are good and safe.
However, when you make the move towards her, that can be seen as more threatening. After all, you are many times her size, so you could hurt her if you made a quick grab for her. She doesn’t want you to do that – but she would still like some food, please.
Give her time. Watch how she behaves, but let her make the first move towards you. When she really accepts you, she will make it clear that further contact is acceptable. But do let her come to you first. Try to imagine how you would feel if you were approached by a giant!
Best of luck with your new friend.
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