This is a world in which only Pokemon live. Many possess the rare and unique ability to transform other mons into living, sentient diapers, gaining the strength and abilities of the transformed mons upon wearing them. Many mons have learned to use this ability for their own benefit, from enhancing their strength to hunting down targets or even selling them as merchandise, with some treating their diapers as partners and others viewing them as equipment.

One day a young trainer by the name of Ash Ketchum would wake up in this world to find himself in this world, transformed into a Pikachu. His partner Pikachu was there with him, transformed himself into a soft, yellow diaper now wrapped snugly around Ash's waist, featuring a pair of bright red cheeks in the front along with a pair of eyes, but no visible mouth.