While there are genuine ads on VS. the great majority have fake pictures lifted straight from porn sites. The more enticing the pictures, the more likely they are to be fake - just how likely is it that a glamour model is going to be advertising on VS? Always Google the phone number, and reverse image search the pictures. Unfortunately there will always be some saps who get reeled in by those pictures. If it looks too good to be true.......
In my experience, the genuine ones will also be advertising elsewhere. If someone is only advertising on VS, you need to be asking yourself why.