Written by Kinoko Nasu.
Chaldea has detected a Singularity at a Japanese hot springs in 2001 with absolutely zero magical elements in it. Normally, they would just let this collapse on its own, given the lack of abnormalities, but da Vinci decided to let Mash and the protagonist go there as a nice way to test Rayshifting. As they travel to the hot springs, they get lost, but a nice man named Shizuki Soujuurou directs them to the path to the inn. The two get lost again as SHEBA updates its analysis of the Singularity, proclaiming there will be no future where humanity survives. They're then attacked by a monster, only to be saved by wandering tourist Aozaki Aoko. She recognizes the protagonist being a summoner who uses Servants and explains herself to also be a mage, with the two agreeing to let her tag along.
At the inn, they discover it's been reputedly haunted for over two years, with the owner thus creating a policy where only exorcists and mediums can check in so the place can be purged of its evil spirits. The three pass a test set by Doctress Kuonji Alice to prove their credentials so they can stay. When Alice asks to see Chaldea summon a Servant after being informed of how they operate, Mash inexplicably summons a teenage Soujuurou from 1991, much younger than the adult they already met in this Singularity. Soujuurou believes being a Servant is just another part-time job for him. Chaldea will have to unravel the mystery of this haunted inn and how the world ends here with only the support of Aoko and their new Servant, Shizuki Soujuurou.
Tropes featured in this story:
- Screw the Rules, I Have Money!: Ryougi Shiki bypassed the inn's current guest policy with her family's wealth and then reserved an entire floor to herself solely so she, her husband, and her daughter could have a nice vacation at this specific inn.
- The Teaser: The story begins with a short section outlining the world ending in Japan on the year 1999 before going to its proper introduction with Chaldea.
- You ALL Look Familiar: Various characters reuse preexisting Servant art. Unlike past events and stories, where it was explained the art reuse came about because the protagonist was trying to process people in a dream Singularity via the people they already knew, it's affirmed that everyone here are genuine flesh-and-blood humans who are strangely identitical to Servants. In addition, Caren, Fujino, Bazett, and Ryougi are the actual characters circa 2001, who have all ended up here for one reason or another.
