IFUMLN

I Fucked Ur Mom Last Night.

Its also know as IFYMLN which is I Fucked Your Mom Last Night.

Steven : Dude bring me some coke
Gianluca: Bring it yourself!
Steven : STFU and bring it to me
Gianluca: Dude IFUMLN so you better show me some respect

IFUMLN by Elepzia January 17, 2010

IFYMLN 

An acronym standing for; I Fucked Your Mom Last Night

P1: hey u
P2:wat
P1:IFYMLN

IFYMLN by some guy doing your mom July 13, 2015