Jintai no Survival!

Geo joins Dr. Know aboard Hippocrates, a tiny exploration craft designed to travel through the human body. Their demonstration takes a disastrous turn when the miniature vessel is accidentally swallowed by Pipi, trapping the two explorers inside her with no easy way back out.

As they navigate the stomach and intestines in search of an escape route, Pipi suddenly becomes ill. Geo can no longer treat the journey as a scientific adventure: surrounded by the workings of a living body, he must risk himself to understand what is wrong and help save his friend from the inside.