Down the drain. Often a metaphor for rivals.
Danny Brown, 2011
Not flushing after urinating, a wiping reference, and a stink comparison aimed at rivals.
Lil Wayne feat. Jae Millz, Gudda Gudda, 2008
A wipe-and-flush joke that treats the Earth as the toilet.
Lil Wayne feat. Jay-Z, 2008
Flushing rivals down the drain, on a Jay-Z collaboration.