The arm/hand not trained in the wiping of the buttocks. In the event of an injury or disablement of the predominantly used appendage, said arm/hand must be called in for back-up. This very often will cause mayhem on the toilet such as constant dropping of the toilet paper in the toilet, wiping in the wrong direction, poo on your hand, crying out obscenities in frustration, uncontrollable sobbing, clogging of your toilet from the constant dropping of the toilet paper and in severe and rare cases one may begin to holler out for someone else to come in and wipe their buttocks for them...in which case would now be called a smeary friendly.
The smeary stranger was used to wipe his buttocks because his right arm was broken and in a cast.
The smeary stranger failed to properly remove poo from his buttocks and eventually he resorted to use of the smeary friendly.