When a man is about to finish in a woman, he can instead cum into a condom to 'load the shotgun'. Once loaded, the loaded 'shotgun' is then placed up to the womans vagina. From here, the back of the 'shotgun' is pulled back and released to fire the shotgun. Results may be messy.
I was so indecisive if I wanted to finish on my girlfriend or not. After she said she wanted it I decided to try the shotgun and it was the highlight of the night!