Ohara zakone (大原雑魚寝)
Ohara zakone is a custom that existed in the Ohara region, where a large number of people would all sleep together in one room on the night of Setsubun (the traditional end of winter) in Efumi-jinja Shrine in Ide, Ohara Village, Atago County, Kyoto Prefecture (present day Oharanomura-cho, Sakyo Ward, Kyoto City).
Summary
According to 'Wakan sansai zue' (an encyclopedia compiled in the Edo period) or 'Yamashiro Meisho Shi (Annals of Yamashiro's picturesque sites), the enshrined deity of Efumi-jinja Shrine is Amenomikudaritama no mikoto, one of the Sanjubanshin (30 guardian deities) in the Imperial Court. And one of the theories says that the deity is Uganomitama no mikoto.
According to a local folk tale, in the deep pools of Ide, there lived a daija (giant snake) that often appeared in the village and ate the villagers. So, all the villagers gathered in one place, lay down and slept together.
This is how Ohara zakone started, according to the 'Ohara Monogatari' (Ohara Story).
In the past, on the night of setsubun the men and women, young and old confined themselves in the haiden (a hall of worship) of Efumi-jinja Shrine, in which their Ubusunagami (guardian deity of one's birthplace) is enshrined, and spent the night.
Therefore, any love affairs on that night would be overlooked.
A poem by Buson YOSA: 'Even nishikigi (burning bush) does not eavesdrop on zakone'