Made a Grunny - You do your business in someone’s toilet and don’t flush it

You do your business in someone’s toilet and don’t flush it while they’re away and wait for the stink to hit them like a brick

I did my business in my uncle’s toilet and left it to rot like a corpse until he got home.

I made a Grunny in my sister’s bathroom and she almost passed out when she came back.

I took a dump in my boss’s toilet and left it to stink up the office like a landfill.