Another owned up to going through their flatmate's phone and laptop when he was not home, while someone else said they have been stealing loo paper rolls from their flattie's room for two years when home alone, and the flatmate had never noticed.
Some of the more innocent confessions included wasting electricity, twerking, and talking out loud to pets when home alone.
"Sometimes I leave all the lights on in my house when roommates aren't home," someone wrote.
"I practise twerking when my roommate is not home. I'm a guy. I'm not gay. I'm just f****** stupid," wrote another.
While someone else confessed to sitting around in the buff. "When my roommate isn't home I sit on her spot on the couch and watch Ellen in the nude."
One of the more concerning responses involved a flatmate who didn't like to use the loo when others were home.
"I have so much social anxiety that I only use the bathroom when my roommate isn't home," someone confessed. And when he's there I pee in bottles in my room."
Some of the secrets were plain weird, like the person who would go into their flatmates room and knock on the walls to annoy neighbours, while another was envious of their flatmates bed.
"My roommate isn't home tonight so I'm sleeping in his bed," they said. "It's so much softer than mine."
As the age-old saying goes, "when the cat's away the mice will play."