rusty mallet 

When a man fake tans his penis resulting in it looking like a rusty mallet. (alternative definition: A heavy hammer object left out in the rain.)

Mike struck me with his rusty mallet this morning.

rusty mallet by Poodefiner June 29, 2014

rusty mullet 

When you pat the vaginal mound in a business like fashion while simultaneously performing enthusiastic analingus.

We were doing the rusty mullet, you know, business in the front, party in the rear.

rusty mullet by Carisatgewise October 12, 2015