In an alternate 21st century, the ancient Tokugawa Shogunate is at the seat of power. An ominous shadow looms over Great Japan, and threatens to engulf the empire whole. Muneakira, a noble samurai summoned by the Tokugawa clan to take over the Yagyu dojo, finds himself as the bearer of an amazing power that he can't control. Things get even crazier when a girl falls from the sky, right onto his lap, and becomes a Master Samurai! Who is she, where did she come from, and why is she so strong? The power is up for grabs as sexy heroines fight to unravel the mystery and save their world on Samurai Girls!