Chisato Satsuki

Living by the sea, protecting the sea, and journeying across the sea…They’re the BLUE MERMAIDS! Because of a shift in tectonic plates around 100 years ago, Japan lost much of its area to submergence. To preserve Japan’s territories, Coastal Cities sprung up, one after the other. Eventually, they became Marine Cities, and along with the expansion of sea-lanes to connect them, the need arose for a sizable staff to protect the seas. At the same time, maritime jobs were becoming more popular among women. Hence, the BLUE MERMAIDS had become every female student’s dream job.

Two Shots adapts the extra chapter of the same name, while All or Nothing adapts Chapter 174 of the same name and a scene of the final chapter of the manga, which also matches with the conclusion of the final episode of the anime series. Two Shots tells the story of how Kurama and Hiei met, while All or Nothing covers a story of the main characters coming back together to solve a hostage crisis in the spirit world.

Bayron City -- a Mega-Float type city in the Pacific Ocean, which doesn't belong to any particular nation. As the mine for Orgonium, a new energy resource, this city is the most noticed in the world right now, and here special cases caused by demons called "D Hazards" has been occurring frequently. Only a handful of people know about the existence of D Hazards. They are handled by PMCs (Private Military Companies). Shu is a young man living in Bayron City who runs such a company, but his company is tiny. On top of that, he cherry-picks his jobs, so he is always in a bind for money. His life, both publicly and privately, is being supported by the beautiful high school girl Kisara who attends a school in Bayron City.