In ancient Japanese folklore, there exists a strange creature known as the kappa. What they enjoy most is not mere mischief, but silently lurking by riversides, searching for people who carelessly approach the water. Legend says that every human body contains a small, round spiritual pearl hidden in the most secret and shameful place—deep within the rectum. This pearl is called the “Shirikodama,” said to be the condensation of a person’s core will and life force.
Once a kappa sets its sights on someone, it will use its slippery tentacles or bizarre organs to forcibly invade the victim’s body. From behind, it slowly stretches, penetrates, and thrusts, as if trying to squeeze and suck the pearl out bit by bit from the deepest part. The process is long and cruel. The person being extracted will feel their body grow hot, tremble uncontrollably, and let out broken moans until the glowing Shirikodama is finally pulled out, wet and glistening, with a soft splash. The one who loses it becomes like an empty shell, their soul seemingly hollowed out, leaving behind a sensitive body that can be violated again at any time.
In modern Japan, these ancient demonic legends have not vanished with the passage of time. Instead, they persist in even more hidden and dangerous forms within the dark corners of the city.
Since ancient times, the legend of the “Shirikodama” has existed—a spiritual crystal of the highest concentration of human spiritual power, buried deep in the most hidden part of the rectum, formed from a person’s will and life force. According to legend, water demons such as kappa would use invasive methods to forcibly extract and pull this spiritual pearl from the body. Once the Shirikodama is lost, the person becomes an empty shell: their consciousness scatters, their body’s sensitivity rises abnormally, they completely lose the ability to resist, and may even become a vessel that nourishes the demons. This ancient method of terror has not disappeared in the present day; it has been inherited and evolved by many other types of evil spirits.
In today’s Japan, countless demons that feed on human bodies or souls remain hidden. They mostly lurk in abandoned river channels, underground sewers, derelict buildings, and dark parks at night—places where the city’s shadows gather. Their forms vary widely, including kappa-type, tentacle-type, parasitic-type, and many other evil beings. They do not appear in large groups. Instead, they use methods such as trapping, paralyzing, and binding to specifically hunt humans who are alone or have weak spiritual power. Once captured, victims are highly likely to suffer the same fate described in legend—being turned into items related to the “Shirikodama,” or becoming long-term nourishment for the demons.
To combat these hidden threats, several specialized academies exist in Japan to train exorcists. The most representative of these is “Shirogami Academy.” On the surface, it appears to be an ordinary higher education institution, but in reality it selects and trains young people who possess spiritual vision or special constitutions. All students are 18 years of age or older. While completing their regular studies, they must undergo rigorous practical exorcism training. The academy organizes students into multiple exorcist squads that are regularly dispatched to various parts of the city to investigate, exorcise, or seal demons.
Exorcism missions always carry extremely high risks. Demons excel not at direct combat but at using the environment, terrain, and special abilities to ambush and capture targets. Once a squad member falls into enemy hands, the physical danger is severe, but even more terrifying is the possibility of being subjected to “Shirikodama”-related rituals or modifications. The academy provides strict warnings and countermeasures during training, yet real encounters are far crueler than any practice.
In the hidden world shared by exorcists and demons, the “Shirikodama” is considered one of the cruelest creations. It does not occur naturally; it is an item crafted by demons through specific rituals and methods, forcibly extracted and processed from a living person’s body.
The general process is as follows: the demon (especially kappa-type, tentacle-type, or parasitic-type water or parasitic creatures) first captures and restrains the target. It then typically uses slippery tentacles, tongue-like organs, or specialized reproductive parts to invade the body directly through the anus. The tentacle or organ travels deep along the rectum, gradually expanding and probing the deepest reaches. Once it reaches the core where spiritual power is most concentrated, it uses suction, wrapping, and squeezing to peel away and pull out the pearl formed from will and spiritual power, finally extracting it completely from inside the rectum.
The extracted “Shirikodama” appears as a smooth, spherical object roughly the size of a fist, with a glossy, wet-looking surface. However, it is no ordinary pearl. It retains and displays the physical features of the extracted individual—such as the facial outline, breast curves, and waist lines of the woman from whom it was taken—appearing as if the entire person has been compressed and sealed inside the sphere. These features are not static; they subtly shift with the fluctuations of the remaining spiritual power within the pearl, carrying a strong visual impression of “being taken.”
After extraction, demons often keep the “Shirikodama” as a trophy or nourishment. The person who loses it becomes an empty shell, completely stripped of the ability to resist.
For the manga about the shirikodama, please click the button to view it🔞：
