I'm sure the "Legends Expanded Universe" people have something about Palpatine intentionally removing the zipper and replacing it with like a jagged catheter that deposits itchy peepee directly in his boot or something, to make him angrier.
Just like there's a machine that removes/places his helmet, his toilet has machinery that removes his codpiece and pulls down his pants for him. It's also equipped with a full-service bidet.
I didn’t have anything fancy in mind, just pulls down the pants or whatever. I think he’s wearing something like robes though. I also don’t have a clue what the state of his equipment is. Whether he’s got anything down there or if its all machine.