Three female runners participate in a marathon, competing for a cash prize. They start off happily, but the water at the refreshment stations has been laced with laxatives. Soon after drinking, they begin to feel severe stomach cramps and desperately try to hold in their bowel movements, their legs crossing tightly as they run. As the pain reaches its peak, just before the finish line, they can no longer resist and soil themselves. Feces drop from under their shorts onto the roadside, staining their white panties brown. This agonizing, humiliating marathon is a first-time experience for them. Enjoy this shocking race, where the limits of defecation and losing control are pushed to the extreme.