You can write a review about your appointment for other people to know that the girl is not a girl but an ugly man. The reviews are visible in user profiles.
You do not need to meet him in the first place if he does not have a lot of good reviews.
But what if the ugly men form a ring and leave good reviews for each other, and since all of them eat their victims, they have no bad reviews to balance it out?
"Conspiracy of the ugly men". Never heard something like this before :) I would not recommend you using the dating sites at all.
How do you get reviews if no one goes to meet you?
Not everybody is scared of meeting other people in real life. If that would be the case, the sites like Couchsurfing would never work.