I'm mainly curious what she's "offering" for this money. For this kind of money, I have to think the guy wants a little more than just "to be the first guy to stick his penis into a strange woman's vagina".
But that's what deflowering a virgin IS. She's offering a guy the chance to be "the first."
Way back in the stone age, when girls married young, the husband was assumed to be the first. But...it was also assumed that the bride (at least) had not had that much experience with ANYTHING, including kissing. Your first night together was...well, the first for a lot of things. Now, "virginity" technically means vaginal intercourse (at least for hetero couples) and some people do "everything but" and still consider themselves "virgins." (NOTE: This can, and does, include anal sex."
This girl is offering her virgin vagina to the highest bidding penis. The draw is that it's the "first penis!"
Whoop-de-do.