The act of insertion of a small projectile (e.g., peanut, dried bean, apple pie-flavored jelly belly jellybean) into the male urethra through the tip of the penis for the purpose of increased stimulation during masturbation and the added effect of rapid projection upon ejaculation.

When you get a blow job while the other person has pop rocks in their mouth.

When your loved one gracefully takes your balls in her mouth while hand stroking your jimmy at the precise moment of making a love puddle...

When your fucking a girl standing up from behind, and you cum so hard it blasts her off your dick like a roman candle firework.

If one is skilled enough, they can actually emulate the action of a real roman candle and do this several times in a row (with a different girl each time of course, since the girl is usually injured on her way back down to earth)

This is what happens right before a man gives a money shot. The act of shaking your penis like a roman candle and having sporatic splooge shots like a roman candle would.

When you put a lighter up your girlfriends butt and light your ciggarette with it