Futanari

Futanari (ふたなり^?, seldom: 二形, 双形, literally: dual form; 二成, 双成, literally: [to be of] two kinds) is the Japanese word for hermaphroditism, which is also used in a broader sense for androgyny.

Beyond Japan, the term is used to describe a commonly pornographic genre of eroge, comics, and anime which includes characters that show both primary sexual characteristics. In today's language it refers almost exclusively to characters who have an overall feminine appearance. In that case the term is also often abbreviated as futa(s), which is occasionally also used as a generalized term for the works itself.

Japanese folk religion created diverse fantasies related to sexual characteristics. Traditional vocal pieces that date back hundreds of years deliver rough evidence that a change of gender was not ruled out and that the representation of the gender was used to worship deities such as dōsojin which sometimes had ambiguous gender, being neither male nor female. Leupp adds that the origins might even reach back to the origins of Buddhism, since the deities would not necessarily have a fixed or determinable gender.

Likewise the belief spread that some people could change their gender depending on the lunar phase. The term half-moon (半月, hangetsu^?) was coined to describe such beings. It is assumed that traditional clothing, which made it more difficult to distinguish men from women like in other cultures, might have had an influence on this development. To restrict women from accessing prohibited areas and to avoid smuggling by hiding items in the belt bag, guard posts were assigned to perform body checks. In historical records, it can be seen that guards liked to joke about this matter quite frequently, resulting in various stories and even poems. Whether anatomical anomalies, like clitoromegaly or unusual physical development, led to these assumptions remains an open question.

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