I feel that you are a good person, but when you ask what's the worst thing that could happen to a girl for turning down a first date........well, one big thing that comes to my mind is becoming a missing person or being found in a shallow grave in the woods! I don't date strangers and I feel safer starting out with a group date and gradually getting to know a person. Rightly or wrongly, we all make decisions based on first impressions. Sometimes we turn down a first date because we feel that we don't have anything in common and we don't want to encourage this person by giving them a false hope. I try to decline in a way that expresses a thank you for asking, but .......(PS: when I decline, I try to let them know that it is fine to ask, but that I have other interest). Then there is another group of people that your inner-self tells you to be leary of.......as a potential source of danger, immoral character or just plain old abusive behavior!