What’s the worst thing a housemate has ever done to your home?

I had a housemate who literally defecated on the bathroom floor in a little line to the toilet set, had left a large pile of poop on it, and left even more in the toilet.

They also used my pots and pans, and took them to their room, only to bring them back weeks later with black mold covering the food. They left the pans in the sink for me to wash (and I only did so because they were my pans).