The protagonist is a girl who has been invited by some boys to spend a night telling ghost stories in an old shrine as a test of courage.
In the middle of the hundredth story, they discover a hidden door in the shrine. After descending an underground path, what they see at the end is...
Legend, a guardian deity, sacrifice.
They had thought this was all a forgotten old tale. But when the sacrificial markings are left on the girl's body, they are once again visited by the guardian deity.
Contains data from VNDB, available under the Open Database License. Reading difficulty and script measurements come from jiten.moe. Statistics are based on daily data dumps and may not reflect real-time changes.