Konpeki no Kantai

In Kyokujitsu no Kantai, Japan builds up on its success in the earlier series by expanding its blue-water capabilities to reach the Atlantic Ocean, challenging the Kriegsmarine in the process. Nazi Germany also launches a surgical strike on the White House and the Japanese fleet repels a German invasion of Britain.

During the cold war, the Japan Maritime Self-Defense Force jointly developed a nuclear submarine with the United States Navy. On its maiden voyage, the captain of the submarine declares the submarine to be an independent state, "Yamato."

Moments after an atomic bomb falls over Hiroshima, a secret Japanese submarine sails into battle against its American counterpart, and both are lost to history. Some fifty years later, a special UN task force sent to investigate unusual phenomena in Antarctica is threatened by a mysterious black cylinder.

In the pre-WWII era, Nakano Naval Academy's special school for girls is codenamed "Virgin Fleet". These girls are gifted with a special form of power known as "Virgin Energy". With the fear of another Russo-Japanese war imminent, rookie pilot Shiokaze Umino must hone her powers to save Japan from complete destruction.