Pedro the Knight had a problem. He had just gotten a suit of mithral +5 full plate of heavy fortification, which was a good thing, except Pedro had been injured in a recent campaign and now had an extremely weak bladder. It would have been extremely humiliating to soil this practically priceless suit of armor, so he couldn’t wear the stupid thing on the account that it took him entirely too long to get in and out of the armor with his medical condition. Also, he didn’t want his nickname to change from “Pedro, Paragon of Perfection” to “Rusty.” Being a rich and successful knight who did not feel it was time to retire and really didn’t want to wear any less than the perfect suit of armor, he decided to spend some money commissioning an item to help solve his problem.
The wizard thought long and hard and came up with the underarmor underwear. This simple item suppresses the biological urge for the subject to urinate and defecate while it is being worn by creating a tiny magical pocket dimension inside the user’s bladder and colon. Pedro loved the item and went back into service, shining bright, and slew fifteen more dragons before he was eventually eaten by an advanced dire, fiendish, half-dragon vampiric badger.
As long as the underarmor underwear is being worn, the user does not have to urinate or defecate. However, if the user wears the item for more than seventy-two hours, the dimensional pocket overflows and the wearer must make a DC 15 Fortitude save or enter toxic shock and die. For each 12 additional hours of wearing the underarmor underwear, the subject must take another Fortitude save at a DC 5 higher than the previous. This is not a poison or death effect, so abilities that prevent those conditions are ineffective. As the underarmor underwear does not actually get rid of the urine or feces, upon removal the user will expel the built up wastes, though with no unusual discomfort beyond what would be accompanied by holding it in for a long time. The underarmor underwear has no other use and cannot create a pocket dimension in any other manner.
People, particularly those with small bladders, will be much more willing to wear heavy armor with this item in their game. Including this item may, for example, increase the number of female knights or paladins in your game world. This item is also useful for a party seeking long term infiltration and not wanting to leave “remains” for the enemy to find. Otherwise, it is a luxury for rich travelers and knights, as well as traditional women who really try to maintain the mystique that women don't have bodily functions.
CL 3rd; Prerequisites: Create Wondrous Item, rope trick; Cost: 24,000 gp