Strict Feeding for my Full Toilet

My slave has to serve me as a full toilet again today and I'm going to be particularly nasty to him today. When he says that he has to pee, I order him to piss in the measuring cup. Then I urinate in and handcuff my slave. I attach a mouth spreader to his cloak, so that I can fill him - no matter how he likes it - with the disgusting mixture...