A hidden Ninja village exists deep in the mountain. Okou (Aimi Satsukawa) who was raised as a lady Ninja is ordered a secret mission by the patriarch.Okou needs to obtain intelligence about Kurobaneshu, the enemy who is planning to destroy the Ninja Village. Okou infiltrates into town and carries out a secret investigation on Togorou (Ryoichi Yuki), a samurai who is suspected to be the enemy boss. However, the more she investigates about Togorou, the more she finds out he is a kind hearted samurai who spare no pains for the neighbourhood. Gradually, they are attracted to each other but find out that Okou is Shinobi and Togorou is a member of Kurobaneshu.