The Japanese have never allowed themselves to stereotype, and this is clear in Japanese shunga art. There are women, there are men, and then there are those of a third gender. This third gender is a person who very often looks like a woman but is actually a young man. These young men, or women, are known as Wakashu Kabuki, and are often seen in the erotic shunga images that are so popular.
Shunga art is not in the least bit pornographic. It is exploratory and it is adventurous, it is always sensual and erotic. There is no stereotyping either. A third gender? Why not? Take a look at some of the images online and have a look at the Wakashu that are often featured, either in woodblock prints or in paintings. They are sensual. They have delicate features and their hair is long, although usually tied up. There may be some clue to their gender in the depiction on the image, whereas sometimes it is left to your imagination. Usually there is a man, a woman, perhaps a scene in a brothel, and in the background, a Wakashu.
Wakashu had a role in Japanese sexual society, and the shunga art shows this role. They were objects of desire by both men and women. They were sensual. And they were wanted.
It is thought that shunga art, while erotic, also does a job. It teaches people about gender and sexuality and reminds them that not all sexuality is the same. Wakashu make people think, as well as think about their own sexuality and their own needs.