When you get oral sex from a woman and you finish inside of her mouth. now she has to swallow and upon
swallowing, you must punch her in
the chest so that she will cough. the desired effect is to make her
cough up the semen and some of it will come out of her nose, therefore the "snorting dragon" reference.
"I gave a
prostitute a snorting dragon because she
charged too much."