Wiping the bowl.

I'm tired of going into the bathroom in my flat only to find that someone has splashed on the toilet seat. Unfortunately for me I cannot leave the bathroom without cleaning it! I absolutely have to clean it solely because I don't want someone to walk in after me and think it were I that acted in such a juvenile way.

"Why the fuck did he not clean that up, who the fuck do you think you are just leaving your piss right there for someone else to have to wipe up. You're not 6 years old for Christ's sakes you rude cunt."

Which is what I think when I walk in and see it.
I mean seriously, it's not that hard. If you want to be a decent flatmate

WIPE UP YOUR OWN PISS!