Its a SICK SICK craze, pursued by youngsters. It involves a gang of youths going up to random people in public or in school and physically victimising them when they least expect it. Meanwhile, one of the gang members is busy filming the violence and stupididity with a video phone, for the gang to laugh at. It is horrible and terrifying for the innocent victim;Hilarious for the sad gang.
Happened to me. Walking down the street at 10pm at night quite innocently on the way home from a club with my younger sister and 2 of her friends when a load of people of about our age started on us. The damage caused was dead painful, and it seemed a lot longer than it probably was. Meanwhile, this wanker said "smile for the camera" and filmed us with a video phone
by A young person from West London February 7, 2005
Get the happy slapmug. The racaus applause your balls make against her cunt when your banging her bare ass as fast as possible.
by LEO March 26, 2003
Get the cunt-slapmug. the act of smacking a vagina in order to inflict painful pleasure. The accepted technique is useful when a girl is on her period, since muff slapping does not involve penetration. Advanced slappers indulge in a pre-slap lick of the fingertips (in order to "get it wet"). Most commonly used on crack whores or slutty broads.
Ryan: Yo, did you fuck that bitch last night?
Evan: Nah she had her period so i got it wet then muff slapped the shit outta her.
Ryan: Tiiiiiiiiiiiiiits!
Evan: Nah she had her period so i got it wet then muff slapped the shit outta her.
Ryan: Tiiiiiiiiiiiiiits!
by get it wet 6 February 17, 2008
Get the muff slapmug. by Bitch-o-matic May 12, 2006
Get the titty slapmug. by goddambats May 30, 2006
Get the boob slapmug. The male act of hitting another with one's genetalia, incorporating the penis, or penis and scrotum, in either an act of foreplay or jest.
by P-Rizzle June 9, 2005
Get the hoagie slapmug. 
Get the johnson slapmug.