In an alternate history of the Meiji era where humans and magical beings known as “younin” live side by side, half-younin girls team up with army lieutenants to fight younin wrongdoers.

Around the the 37th year of the Meiji Era (1904) in the midst of the Russo-Japanese war, the small Japanese army, in need of assistance, uses its special flying (thanks to a benevolent demon) ship, the Amanohara, to attack Russia’s major base at Port Arthur (Lushun). Umakai Shintaro, a Russian diplomat originally from Japan, defects and goes to Sapporo to teach at a girls academy. However, that girls academy is not typical – it is on board the Amanohara, and the five girls Shintaro teaches are known as the Raimu Unit – girls with the ability to summon powerful beings to fight for them. Shintaro eventually becomes their teacher and general in battle, and so the six embark on a weird and excessively erotic journey, as Shintaro helps the girls overcome their weaknesses, become stronger for the final stand at Lushun, and also understand the motives of the “Russian Spiritual Corps” that assist the opponent, which, unfortunately, has one member whom Shintaro knew well….

The original story follows the human drama of the Yamazaki family in Tokyo in the Year Shouwa 39 (1964) — the year that the city hosted the Summer Olympics.The Yamazaki family lives in Tokyo. Its members are Yuuzou, the father, Kanoko, the mother, Yoshi, the grandmother, Taichi, eldest son and university student, Yuuko, eldest daughter and high-school student, and Kouhei, the youngest sibling and primary school student.Currently, the Yamazaki family is in a state of flux and discord. However, they are brought together by the activities and festivities surrounding the Tokyo Olympics.

Plot Summary:Kasumi Kenshiro, also known as Yan Wang or the King of Death, is a Tokyo professor and the 62nd successor to the deadly assassin art known as Hokuto Shinken. He leaves his teaching job and travels to Shanghai after getting word that his old Qing Bang Triad friend, Pan Guang-Lin, and his friend’s sister and Kasumi’s love interest, Pan Yu-Ling, are in trouble. While in Shanghai, he encounters and fights the three families of Hokuto: Hokuto Sonkaken, Hokuto Soukaken, and Hokuto Ryuukaken. He does all this while revolting against the corrupt Hong Hua Triads to restore honor and power to the Qing Bang.

The story is set in Shanghai in 1931, when the Imperial Japanese Army has been dispatched to mainland China due to the relatively recent First Sino-Japanese War, Russo-Japanese War, and World War I. In this cosmopolitan city of intrigue, there is a special military spy organization called “Sakurai Kikan” that has since been buried in history.