Need help plotting revenge

I have an awful housemate. If I ask them to clean up their messes they curse at me and say they’re too depressed. Dishes regularly pile up in the sink and I am forced to do them all. They also don’t shower for days and their stench is so strong you can smell them from different rooms in the apartment. Their cat shits on my things and they refuse to clean them. They use my bathroom even though they have their own and leave stains in and on the outlet as well as pubes. They have also started malicious rumors about me and tried to turn people in my life against me. I am sick and tired of them and need them to get what’s coming to them. What are some ideas for revenge that can’t get traced back to me?