Fertility festivals, sex festivals. Many shrine festivals (hadaka matsuri, mikoshi contests etc.) are evidently meant in part as displays of manhood by those of marriageable age. In some festivals sexual and fertility symbolism predominates. At the Asuka-niimasu jinja, Nara on the first Sunday in February actors representing a form of dosojin couple wearing otafuku and saruda-hiko masks enact sexual intercourse. At the Sugawara jinja, Niigata, the tsuburo-sashi kagura performed on June 15th unites a male divinity holding a giant phallus with a female kami playing a sasara (a percussion instrument consisting of two blocks of wood). The honen ('abundant-year') matsuri of the Tagata jinja, Aichi on March 15th features a parade of large (4-5 metre) and extremely lifelike wooden phalluses carried on mikoshi. The michi-no-kami (kami of the roads) are worshipped in numerous 'phallic' shrines such as ebishima jinja and dosojin jinja.
A Popular Dictionary of Shinto. Brian Bocking.