The Kaijin is a cryptid

Cryptid

In cryptozoology and sometimes in cryptobotany, a cryptid is a creature or plant whose existence has been suggested but is unrecognized by scientific consensus and often regarded as highly unlikely. Famous examples include the Yeti in the Himalayas and the Loch Ness Monster in...

, an alleged sea monster

Sea monster

Sea monsters are sea-dwelling mythical or legendary creatures, often believed to be of immense size.Marine monsters can take many forms, including sea dragons, sea serpents, or multi-armed beasts. They can be slimy or scaly and are often pictured threatening ships or spouting jets of water...

 living in Japan

Japan

Japan is an island nation in East Asia. Located in the Pacific Ocean, it lies to the east of the Sea of Japan, China, North Korea, South Korea and Russia, stretching from the Sea of Okhotsk in the north to the East China Sea and Taiwan in the south...

. It is mentioned in the books of the Edo period

Edo period

The , or , is a division of Japanese history which was ruled by the shoguns of the Tokugawa family, running from 1603 to 1868. The political entity of this period was the Tokugawa shogunate....

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Overview

According to a Japanese Materia medica

Materia medica

Materia medica is a Latin medical term for the body of collected knowledge about the therapeutic properties of any substance used for healing . The term 'materia medica' derived from the title of a work by the Ancient Greek physician Pedanius Dioscorides in the 1st century AD, De materia medica libre...

, he was almost close to a man, in addition to chin hair and eyebrows, between the fingers and limbs is a description of some skin. He ate food and drank but never spoke.

According to Nagasaki

Nagasaki

is the capital and the largest city of Nagasaki Prefecture on the island of Kyushu in Japan. Nagasaki was founded by the Portuguese in the second half of the 16th century on the site of a small fishing village, formerly part of Nishisonogi District...

's records, in addition to these features, there was probably a Hakama

Hakama

are a type of traditional Japanese clothing. They were originally worn only by men, but today they are worn by both sexes. Hakama are tied at the waist and fall approximately to the ankles. Hakama are worn over a kimono ....

 and a flap of skin around the waist, and they could live for only a few days on the ground, after coming up from the sea. One theory suggests that it was a Sealion or seal

Pinniped

Pinnipeds or fin-footed mammals are a widely distributed and diverse group of semiaquatic marine mammals comprising the families Odobenidae , Otariidae , and Phocidae .-Overview: Pinnipeds are typically sleek-bodied and barrel-shaped...

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Many Japanese legends say that Kaijin-sama is a kaze-kami (species of god of the winds) and it appears inside the clouds in a purple cloud, taking sacrifices in every village to calm down the winds.