0?

You don't necessarily have to tell someone to stop outright, you can just sort of get out of there, lol. For example, moving away. Answering questions about why one is resisting is acceptable though.

'Stop' is a command, I don't really like to command people, it's something you fall back on when flustered. One should prepare on how to more calmly deal with situations like this so you don't have to hurt people's feelings by saying something so abrupt to reject them.