Welcome to the world of うんコレ! After being flushed down the toilet and passing through a dark tunnel, you find yourself in a world called "ウントピア," where people live with bacteria inhabiting their intestines.

You are the chosen savior who has arrived in this world. It may seem impossible, but you have a special kind of intestinal bacteria that sets you apart. There is no other way for you but to fight alongside your bacteria as a chosen member of this world, known as a "Medium." Please protect ウントピア, as it will surely benefit you as well.

Your enemies are called "クリーブス," a new species. Where did they come from? How are they multiplying? Why are they trying to destroy ウントピア? No one knows.

One thing is certain: only you can protect ウントピア and your own body. It may be hard to comprehend being called a savior all of a sudden, so please take the time to understand the world of うんコレ and join us firmly. We wish for the health and peaceful bowel movements of the world. Kaanbeen!