rusty lining
The opposite of a silver lining. It's finding the bad in a good situation.
Person: I'm so happy man. I got an A+ on the math test!
Person's Friend: Only cuz you cheated
Person: Man, why do you always look for the rusty lining?
Person's Friend: Because it's true
Person's Friend: Only cuz you cheated
Person: Man, why do you always look for the rusty lining?
Person's Friend: Because it's true