A greek virgin is a geek male, who only apparently gets laid when no one is around. YOu have never seen this male with a female companion, however when he goes to Greece and no friends are around he comes back with stories that he has had sexual encounters with multiple women. A greek virgin is the loser of the group, never gets any action, but miraculously everytime no one is around he is an alpha male and has all kinds of sexual encounter stories with multiple females.
Friend goes to greece, comes back telling you he slept with 7 girls. GREEK VIRGIN
Everytime you go out, he is watchign you get action. When you are not around, he is the biggest stud. GREEK VIRGIN
You can also refer to guys like this by their first name. Ie BILL VIRGIN! But for this to apply they have to be greek.