Shit on your Skittles
Comparable to the phrase "rain on your parade"; something that brings you down and/or sucks in a major way.
Sally, you look so sad. I wonder who shit on your Skittles?
You know, I was having a great day... don't come over here and shit on my Skittles, butthole.
You know, I was having a great day... don't come over here and shit on my Skittles, butthole.