My new coworker brought a “chicken casserole” to the office potluck and really wanted everyone to try it. A few hours later, everyone got sick and left, but I stayed since I didn’t eat it. That’s when I smelled something terrible coming from her desk.

I opened the drawer and found dozens of packets of expired mayonnaise that had spilled in the heat. Some were open and empty. It seemed she used them to make the creamy sauce that made everyone sick. The drawer also had other gross things, like fingernails and dirty napkins.
She had only been with the company for a few weeks and didn’t seem unclean at first. I’m not one to tell on people, but I had to report it to HR. She was fired a week later.