Look here! This aerial photo shows a large lake located in Suwa... But there's an unnaturally round cavity right here.
This itself is a plenty mysterious occult spot... But there's also theories that there used to be a shrine there...
There's this unsolved case that happened in the same region around the same time. A disappeared schoolgirl.
There were rumors that she might've been spirited away or something, but... Some of those rumors gave her a nickname...