In a certain time in a certain world, where samurai swing swords and the Tokuyama Shogunate wields absolute power. The legendary swordsmith Hiraga Mei has on the order of the shogunate forged 12 soul swords. Those swords take the form of women, and hold the power to crush a country with one swing by their beloved samurai. His father, Hiraga, was killed by someone, so Soregashi Tatsumi will avenge him. Alongside Nanashi, one of the swords Hiraga made, he challenges the Shogunate.
