YOU SAID:
The cats came to the party to pee in the litterbox
INTO JAPANESE
猫はトイレに小便をするためにパーティーに来ました
BACK INTO ENGLISH
The cat came to a party to piss in the toilet
INTO JAPANESE
猫はトイレで小便をするパーティーに来ました
BACK INTO ENGLISH
The cat came to a party to piss in the toilet
Okay, I get it, you like Translation Party.