When someone thinks they must far, but accidentally do so with such force that it leaves a chartreuse color paste in their underwear, a mixture of blood and diarrhea.
A state of mind-bowel agreement where the the mind of the individual realizes it cannot allow a fart to occur because there is a realdanger of sharting one's self.
After calculating the odd's of sharting due to the unstable state of his anus, Manny and his mind called a "shartruce" with his bowels until he could reach a comode.