From Evil Flowers:

Fukka, the daughter of the Inuiyama's lord, is determinate to do everything to help her father win the war and get him home safely. Because she's a girl she's not allowed to go to the battle field with him, but she hears about a certain "war ghost" called Byakkimaru has been seen near her town. The legend says that if you get Byakkimaru to join your side you will win the war. The little princess starts a trip in search of this ghost determined to save her clan.