shit in (one's) Cheerios(redirected from shat in her Cheerios)
shit in (one's) Cheerios
vulgar slang To upset, irritate, or disappoint one to a great degree. A more vulgar but less common variant of "piss in one's Cheerios." Sorry to shit in your Cheerios, but you won't get any credits for the class unless you attend every single lecture. A: "Watch out, the boss is in a foul mood today." B: "Wow, I wonder who shit in his Cheerios?"
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.