The figure may depict Urashima Taro, a hero of a popular Japanese fairy tale. He is depicted in various guises, one as an old man with wrinkled face, sometimes as a fisherman with a box, or upon a tortoise.
Urashima was a crab-fisher of Midzu no Ye, (Ejima) in the Yosa district of the province of Tango. In the second year of Teneho (AD 447) he fished a tortoise, but instead of killing the animal he good naturedly put it back into the water. It so transpired that this tortoise was no less than Otohine, a princess of high rank, whom he later married. The complete story appears in the Manngo Shiu. See Henri Lodoly, Legend in Japanese Art, Tokyo, 1967, pp. 548-549