the dream of the fisherman's wife
The Dream of the Fisherman's Wife (蛸と海女, Tako to ama, Octopuses and Shelldiver) is an erotic woodcut of the ukiyo-e genre made around 1820 by the Japanese artist Katsushika Hokusai.
Perhaps the first historic instance of tentacle eroticism in art, it depicts a woman entwined sexually with a pair of octopodes, the smaller of which wraps one of its tentacles around the woman's nipple and kisses her, while the larger one performs cunnilingus.