You really have to pee, like really, really bad. You can't hold it in anymore, but there is no toilet in this stall, but you don't want to make a mess in your underwear and pants or on the ground either. There is no Toilet here, but it looks like there are buttons on the wall and a trapdoor on the floor.
"OOOOOOOOH!" you say, you really, really need to go now so you hit the cow button. The floor near you opens up and you see what looks like a Milk pail.
"ARE YOU KIDDING ME!" You say. They really expect you to squat down and take a piss in it? Well, it looks like there are no other alternatives, so it seems that you have to.
You do so and you begin to urinate out the things in your bladder. However, it is not yellow urine, instead it is thick, white, and creamy. You are scared, but you reluctantly take a drink from the bucket after you are done peeing. It is not disgusting like cum, but it is delicious cow milk.
"OH NO!" You say, it is cow milk. You just peed milk out of your human urinary system including your bladder and human urethra. Your human urinary system like your Bladder is now just a giant Mammary gland. This is so humiliating. But it does not end there.