When you are trying to have anal sex with a women or man, and you cant get your penis in, the person shits and their poo acts like a lubricant so your penis will just slide in.
Man: Fuk i cant get my penis is your butthole Women: Ok one sec, let me shit so my feces will act like lube.............aaaahhhhh phphphpppphphp
Man: OH YA, its in!!!!!! This is what I call a Shitfuck!!!!!!!
Traditionally, when one person pushes excrement out of their anus directly into their partner's anus. Shitfucking can also be performed into other orifices. For instance, one can shitfuck a mouth.
"While I am no Clinton lover it's pretty much inarguable, he was miles away better as President than Shitfuck."
"George Bush was explaining what 'his job is' in various speeches and press conferences. I.e., 'you know, one of the hardest parts of my job is to connect Iraq to the war on terror'. No shit, Shitfuck."
"When he was Ambassador to the Saudis did he kiss and hold hands with Abdullah like Shitfuck did and does?"