Twin sisters, Mio Amakura and Mayu Amakura, visit the Stream of Memories.

Soon, this entire area will be flooded by a dam…

As Mio drifts into nostalgia, her sister Mayu is lured away by a crimson butterfly, leading her into a “village erased from the map”.

There, vengeful spirits roam—souls forever bound in search of the twins who once fled from a sacred ritual. Trapped in a place where night never ends, Mio sets out to find Mayu and escape the cursed village.

But in doing so, she unknowingly retraces the path of a past tragedy—
and deep within the village, she comes face to face with the forbidden ritual that should never have been seen…