The residue of poo left above the upper lip where a regular mustache would be located. The 'crapstache' can appear after an individual gives the bung tung to another individual. It can also appear after someone rubs his or her lip after wiping poo with his/her hand.
After a night on the town, Phillip spend the night with a ho fo sho. He awoke the next morning with a crapstache.