loin gravy 

Combination of ass sweat and fecal remnant that combine in the crack of the ass during periods of physical exertion. The condition occurs most often in adult men as fecal remnant is often found in dense pubic hair growth of male ass crack. See also waiter's crack.

After mowing the lawn in the summer heat, Todd found he had whipped up a hefty batch of loin gravy.

loin gravy by Jake September 8, 2004