I've run into a situation where my main character has met someone who is very important to the plot. This guy has sort of just approached her and introduced himself at a cafe. My issue is I'm not entirely sure how someone like my main would naturally react to that. I'm kind of a distrusting person when it comes to strangers, polite, but I don't like interacting with people face to face. My main character is kind of the opposite in that she's sweet and open to everyone. I'm not really sure how to write that in, but I don't want to change my main character. Any advice?