Rinkan Club: First Volume.

There was a dark ritual that has been handed down for over a thousand years in the mountain town of Hayashigaku. In order to calm the angry god, a collection of women who were supposed to be shrine maidens was brought together, and as a result, if the shrine maiden was conceived, the god would calm the anger and promise peace and fertility, and the shrine maiden who was not conceived filled the spirit of the man. It was wrapped in straw and swept alive into the river, where it was sacrificed by a god. And now --- the ritual has not disappeared into the darkness of history and has continued to live in the only school in Hayashikaku City, and its miserable tradition has been inherited as a secret society "Rinkan Club".