The Unnatural Bureau of Mountains and Seas

The summer that Airi graduated from college at the age of 22, she insisted on joining the graduation trip organized by the girl she had a crush on. Meanwhile, her parents took her younger sister, who had just finished the college entrance exam, on an ocean cruise. Who could have guessed that the cruise ship would inexplicably vanish in international waters, as if a hundred-thousand-ton vessel were no more than a wisp of insignificant smoke? From then on, the course of Airi's life changed completely, and she became locked in a battle with the sea. Eight years later, Airi, now a deep-diving expert, dives yet again into the waters where the cruise ship's radio signals disappeared. This time, as if guided by some unseen force, she seems to see an abyss opening on the ocean floor, one that can swallow even light. She touches the abyss, and in doing so enters another world...

Connecting to the "Anomaly Handling Protocol v2.0"...

[Insufficient protocol access. Upgrading to processing under the Hetu System...]

Versatile, fearless, and rebellious field agent (former occupations: navigator, deep-sea diver, private chef) V Chaste, highly educated, and worrywart team leader (former occupation: thoracic surgeon)

Updates will begin on November 6, 2026. Stay tuned.

Reader's guide: 1. Dark Classic of Mountains and Seas + Foundation containment + System. There are superpowered battles. Only the Foundation's creative framework is referenced; all content is original, with no harmful influence. Fundamentalist purists, please stay away.

2. This is an alternate-universe setting, with a level of development comparable to the real world. Basic world information is borrowed from reality, but the story is unrelated to the real world.

3. One-on-one romance, a deep bond between bickering rivals, and a somewhat slow burn.

Theme: There will always be someone to hold open the rift between the mountains and seas and the world of the living