Anyone who sends nude pics to a stranger knows there’s a risk that goes along with such a bold move. The person, even if they’re real, can turn on you and become spiteful, sharing the pic to embarrass you.
Or, in this case, the person you were talking to the entire time turns out to be a scammer who, once they get your pic, blackmails you by threatening to spread it unless you pay them.
Of course, there’s no guarantee that paying them will keep them from sharing it. There’s also no guarantee that they’re actually going to spread it.
Taking a chance, the guy getting blackmailed decided to have a little fun by tormenting his blackmailer with EVERY. LITTLE. DETAIL.