Knullar

"to fuck" in Swedish.

"Baby du knullar bra"-Snook
"Baby you fuck well"

jag knullar din mamma

Swedish for "I'm fucking your mother". Not literally ofcourse. mostly. It's more likely to be used as an insult instead of being a statement.

Guy: Jag knullar din mamma!!
Me: Då är vi kvitt.