In the year 2205, a special sage known as Saniwa possesses the ability to breathe life into inanimate objects. Simultaneously, dark forces have launched a plot to travel back in time and alter the course of history—and the only ones capable of stopping them are the Saniwa and their most powerful animations: historical Japanese swords, appearing as handsome young men. Touken Ranbu: Hanamaru begins with the life of Yamatonokami Yasusada, Souji Okita's beloved uchigatana, as he starts his first day at the Saniwa's citadel. After soon reuniting with his old friend, Kashuu Kiyomitsu, the two become involved in the daily antics of their fellow sword warriors. They never miss a chance to have fun, whether through wild snowball fights or introducing their newest comrades to the citadel. Naturally, when the government calls, the swords are always ready to fulfill their mission of protecting history.