The Klein Bottle of a Certain Chaldea

After retiring, Akae Natsuki is recalled by his creator, "Book," to resume his role as a savior. However, his mission shifts from saving his own world to saving parallel worlds.

On his first day back on the job, Akae Natsuki is transported to a mission world and accidentally impales a staunch materialist, Anshitsu, with a spiritual entity. The materialist loses his convictions in an instant, while the spiritual entity, feigning innocence, gives a chilling smile.

"Hi, your spiritual entity express delivery—please sign for it?"

Anshitsu: …?

The amnesiac spiritual entity appears in Anshitsu's life, and they decide to find a way to break this inexplicable bond. Their journey ends with a Ferris wheel, carrying the truth from eight years ago, sinking into the sea. The rescued Anshitsu calls out the spiritual entity's name, but only the sound of waves remains.

"Next time, let's go to the amusement park together, okay?"

In a magical Tokyo where everyone can transform into small animals, the mysterious cat café owner is revealed to be the heir of a dog-loving black organization, plotting to destroy all cats with catnip and chocolate.

The red organization, fighting against the air, responds: "That's your plan?"

Crowd: Overthrow the evil human regime! The world belongs to the organization! … (turning head) Oh, what's our organization called again? Endangered Species Protection Organization?

Old man U: Roll!

The café owner smiles innocently at the camera: "What kidnapping? I just want to give everyone a warm home."

Other adventures include a three-year-old with 10,571 clones, a Tokyo bat hero saving the city from the abyss, a high school detective opening a surprise egg at an amusement park, and a demonic savior becoming the villain to prevent his friend from turning evil.

Akae Natsuki himself says: "I'm having a lot of fun, too much fun to think about returning."

In his main world, after seeing the true fourth Grail War in his dreams, Shitaga wakes up in a cold sweat.

Upcoming Works:

"Officer Kudo Has No Comment"

Kudo is suddenly bound by a system that forces him to role-play in the main world. He agrees, on the condition that he controls all aspects of the missions. However, the system often disagrees with his scripts.

—

Examples:

In a bar, a purple-eyed youth orders a glass of Tennessee whiskey and smiles at the golden-haired undercover agent next to him: "Tennessee drinking Tennessee… isn't that interesting?"

System: ?

Kudo: Let me introduce, this is my subordinate, Sato from the Investigation Division.

In a hospital, a man resembling a gangster sits on the stairs, ignoring the public security bureau chief in front of him, and smirks: "A bomb? Oh, I made it. Very intricate design, isn't it?"

System: ?!

Kudo: Meet our explosives expert, Special Consultant Matsuda from the Police Department.

In a dark alley, a Scottish man holds a gun to Kudo's back and says coldly: "My specialty isn't just sniping, traitor."

System: How do you explain this?!

Kudo: This is the famous actor Hakuya, who is currently filming a crime drama.

System: But isn't your world a peaceful one?! Are there any characters that won't be misunderstood?!

Kudo looks at the remaining cosplay scripts and gives a innocent Conan-like expression.

— Which one should I choose? Public Security Officer Akechi, Preschool Teacher Kuroba, or myself, the savior of the police world?

Anshitsu is currently feeling very depressed. He feels like he's in trouble. Moreover, he's noticed that his strange classmates all mention the same entity.

"My boss is very powerful, you know?"

"Ha, Mr. Shinichi is my mentor."

"… That person is like family to me."

At this moment, Conan pushes open the door of Café Poirot, looking serious, as if he's encountered something incredible.

Conan, anxious: "Mr. Anshitsu—!"

"…"

Conan, sweating: "Mr., Mr. Anshitsu?"

"……"

— Why are you washing dishes with such a grim expression while looking at me?!

Reading Notes:

Kudo has no romantic interests; Shinichi is still a child.

The characters Kudo role-plays are based on his own world, specifically Kudo 1.0.

There is no red-to-black transformation setting; everyone is good, just wearing a Yomiuri filter.

Everyone survives.

The story focuses on Kudo shocking others in the main world.

Content Tags: Fast-paced, Wild, Chaldea, Mask, Light-hearted, Fourth Grail War

One-Sentence Summary:

A full-fledged savior's retirement and re-employment adventure.

Theme:

Those who know the future change the world; pioneers create the future.