Ashinaga-Tenaga are a pair of very human-like monsters of Japanese folklore. One has extremely long legs, while the other has extremely long arms. The two work together as a team to hunt fish and small animals. The sighting of these monsters is said to bring bad weather.
They are usually sight near streams or rivers and it seems that they have a deep connection with the water, able to commune with the water around them to turn the land into a sea of mud. These yokai (supernatural monsters/creatures), long a legend among the peasants of the Ro-Kan, their exact motivations for joining the fray are unknown but they are a welcome boost to the morale of the villagers they appear to protect.
Their presence gives a sense of belief in the common people enabling them to fight harder in defense of the balance of Jwar. To look at them individually one would think that they lack any combat skill, but once combined, one astride the other, the pair are a tricky opponent. With a snaring net in one hand which they use to either entangle an enemy up close or from afar, in the other a diamond sharp fishing spear handled with great precision.
Ashinaga-tenaga are are commonly described as people from two countries, the Long-legged Country, and the Long-armed Country.
The two work together as a team to catch fish by the seashore. In order to do this, the long-armed man, Tenaga, climbs onto the back of the long-legged man, Ashinaga. The Ashinaga then wades out into deeper waters, staying above water with his long legs, while the Tenaga uses his long arms to grab fish from his partner's back.
According to the Wakan Sansai Zue, Tenaga’s arms can reach three jō in length, or a bit over nine meters, while Ashinaga's legs stretch to two jō, or just slightly over six meters.
An essay from the Kasshiyawa by Matsura Seizan also describes the Ashinagain by documenting an encounter between a man and the strange being. The man was fishing by the seashore on a clear, moonlit night, when he spots a figure with long legs (about 2.7 roaming around on the beach. Shortly after, the weather turned bad and began to rain heavily. The man's servant then informs him that they had just seen an Ashinaga, and that sightings of this yōkai always brought bad changes in weather.
-Ashkenazi, M. (2003). Handbook of Japanese mythology. ABC-CLIO.