High School Fleet

The genesis of High School Fleet lies in a twist on Japanese history:

Ryoma Sakamoto survives an assassination and steers Japan towards becoming a maritime nation,

leading to a unique parallel world where sprawling sea cities and advanced naval organizations form core pieces of society.

The concept was shrouded in mystery at first—promoted simply as “Haifuri” and giving off a slice-of-life vibe,

with the naval angle only revealed in episode one.

Production IMS produced the anime, with AAS (AIS) as the original creator,

Reiko Yoshida handling series composition, with characters originally designed by Atto.

Japan, and much of the world, is drastically changed due to land subsidence.

Sea level rise has resulted in a culture centered around giant floating cities and extensive marine routes.

Blue Mermaids are a prestigious, all-female maritime security and rescue corps.

Girls train at specialized marine high schools — like Yokosuka Girls’ Marine School,

the main setting. The world diverged from real history after the survival of Ryoma Sakamoto,

ushering in a greater reliance on sea power, and no World War II ever occurring.

Technology is semi-advanced: aircraft and missiles were never realized,

instead airships fill that gap, and war era ships—from Yamato to Admiral Graf Spee—are used for training.

Navigation depends on satellite-less systems akin to TACAN (not GPS), and guided torpedoes,

not missiles, are the apex of long-range ship-to-ship weaponry.

Akeno Misaki (Ake-chan) witnessed the Blue Mermaids’ Yamato as a child with her childhood friend Moeka China.

They vowed to become Blue Mermaids together.

Years later, they enroll at Yokosuka Girls’ Marine School,

each appointed as captain of a different training ship (Harekaze for Akeno, Musashi for Moeka).

On their maiden voyage, Harekaze arrives late for exercises and is suddenly attacked by their own teacher.

Defending themselves, they’re accused of mutiny and forced to flee—from both their own academy and external threats.

As their journey unfolds, mysterious outbreaks amongst other ships turn friendly ships hostile,

and the crew dives into increasingly dangerous and heart-pounding missions.

Through each crisis — from torpedo duels to raging storms to bizarre animal-borne viruses —

Akeno, Mashiro Munetani, Kouko Nosa, Mei Irizaki, Shima Tateishi, Rin Shiretoko, and the rest of their colorful class

adapt, bond, and carve out a quirky, unbeatable team.

Blue Mermaid

Japan’s (and the world’s) premier all-female maritime defense and rescue force.

Founded by Ryoma Sakamoto’s sister and wives of the Kaientai, the organization is an international presence—

a dream job for marine-school girls.

Yokosuka Girls’ Marine School

A marine high school that trains future Blue Mermaids—one of four schools (others are in Kure, Maizuru, Sasebo).

Each class manages a single historic warship as a training ship.

Graduates are guaranteed a position in the Blue Mermaids.

Harekaze

The Kagero-class destroyer used by the main cast as their training ship.

Equipped with advanced radar and automated turrets, it’s regularly beset by engine trouble but is crucial in every pinch.

RATt Virus

A genetically engineered, hamster-like animal carrying a mind-altering virus.

Infected shipmates turn aggressive and act in concert, causing chaos.

The virus also emits electromagnetic fields that disable ship electronics.

Skitters

Futuristic water scooters piloted by trained students, used for both rescue and battle.

Anime TV Series

12 episodes aired from April to June 2016.

Followed by two OVA episodes and “Haifuri” manga serializations.

Movie

Released in January 2020, the film continues the story with a major maritime crisis —

involving international students and a powerful marine fortress hijacked by pirates.

Manga

Several series:

• “Haifuri” (High School Fleet): Slices-of-life and comedic backstories, currently at 12 volumes.
• “High School Fleet: Maidens of Lorelei”: Spinoff focusing on Wilhelmina’s youth.

Game

A mobile game “High School Fleet: Pinch in Fleet Battle!” was released for iOS/Android, running from March 2019 to March 2020.

Novel

Light novels expand upon in-between stories, including “Interval” and “Arrival”.

Pachinko/Slot Machines

Officially licensed machines featuring characters and warships have been produced since 2018.

Web Radio

“Akeno and Mashiro’s High School Fleet Radio – Harekaze Internal Broadcast” was streamed weekly to engage fans.

The staff includes:

• Original story by AIS (later AAS)
• Scenario by Reiko Yoshida and Takayuki Suzuki
• Direction by Yuu Nobuta
• Character design by Atto (original), animated by Naoto Nakamura
• Music composed by Shigeo Komori

Major animation production was by Production IMS for the TV/OVA, and A-1 Pictures for the film.

Voice casting featured top-tier Japanese voice actresses, many known for later prominent roles.

The anime’s initial “Haifuri” (an abbreviation) title created buzz,

with the ship and naval aspects kept secret in early trailers, generating surprise and hype at the episode one reveal.

• Opening: "High Free Spirits" by TrySail — an energetic and catchy anthem, voted “Best Theme Song” at the 2016 Newtype Anime Awards.
• Ending: "Ripple Effect" by Luna Haruna
• Movie Theme: "Free Turn" by TrySail

Insert themes and character songs have also been released, with strong performances by the cast’s vocal unit.

“High Free Spirits” won the 2016 Newtype Anime Award for Theme Song of the Year.

High School Fleet enjoyed significant popularity for its unique blend of moé character antics and serious naval action.

The clever use of real-world ship designs and detailed worldbuilding attracted both anime fans and naval enthusiasts.

Regions featured in the anime, particularly Yokosuka, saw a boost in tourism thanks to extensive collaboration events,

stamp rallies, and themed merchandise.

Multiple tie-in events with JR East, local shops, and real navy-port facilities reinforced its presence in pop culture,

cementing Haifuri as a fun, memorable entry in the “girls & ships” anime genre.

The franchise extended into other media, such as the game “World of Warships” which featured official Haifuri-themed ships and characters.

Staff and creators often revealed that the show’s foundation borrowed from alternate-history works by Takayuki Suzuki,

blending real and fanciful maritime technology with energetic schoolgirl drama.

If you’re curious about quirky camaraderie, explosive sea action, and a setting lovingly built on “what if” naval history,

High School Fleet is definitely worth boarding!