Tanegaike Dragon
The Bentengu is a shrine to Benzaiten on the shore of Tanegaike, a small lake close to the sand dunes in Tottori. Though only a quarter of a square kilometer in area, the lake is actually the deepest in the Chugoku region, with a depth of 17 meters. Deep in the lake lives a serpent.
Once upon a time a local rich man employed many local villagers as servants. One young woman, who of course was beautiful, by the name of Otane was employed as a maid. Otane was known as a particularly kind and generous young lady and every day she would give people persimmons.
One young man was curious about where she was getting the persimmons from so he secretly followed her. She went down to the shore of the lake and transformed into a serpent and then swam out to a small island in the middle of the lake and picked persimmons from a tree there.
Because she saw the young man watching her she was unable to turn back into her human form and so stayed as a serpent living in the lake.
An old lady built a small shrine to honor Otane, and this grew into the Benzaiten shrine. Benzaiten, originally the Hindu goddess Saraswati, has strong associations with water and therefore also serpents. She is one of the seven lucky gods of japan and has both "shinto" and Buddhist manifestations.