When Yui Kusunoki, an undercover geisha secretly in the employ of the Inner Secret Guard, disappears while en route to deliver an oral message concerning rogue Koga Ninja penetrations in southern Hikone, there's just one sword-mistress who can go down after her: the notorious but very easy on the eyes Rin Saejima a.k.a. the Sultry Assassin! But knowing that her identity may have already been compromised as a result of the Koga's Erotic Brainwashing technique, Rin devises a cunning plan of her ow...