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An annual festival has been held in Kawasaki, Japan, to celebrate a 17th century tale about a steel phallus that defeated a demon.

The festival involves a mikoshi parade through Kawasaki, in which large phalluses are transported, centred around a local shrine which has been historically popular among prostitutes who prayed there for protection from sexually transmitted infections.

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The accompanying 17th century legend goes thus:

A sharp-toothed demon hid inside the vagina of a young woman who wedded two men. On both wedding nights, the demon castrated the men by biting their pensises off.

The young woman sought help, which came from a blacksmith who made an iron phallus.

Picture: Chris McGrath/Getty Images

The demon bit down on the phallus and broke his teeth, and was thus vanquished. The phallus was subsequently enshrined.

The festival began in 1977, originally a small affair, but has grown in recent years and is used to raise money for research into HIV.

People from around the world visit the festival, to eat phallic sweets, see the statues and carved vegetables, decorations and parade.

Picture: TORU YAMANAKA/AFP/Getty Images