Hinowa ga CRUSH! Series by Takahiro

On the island of Wakoku, the civil war offers anyone the chance of becoming a hero -- from fishing women to bastard children, any can make a name for themselves by working through the rigorous ranks of the army. Hinowa, a young woman with extraordinary skills, is determined to do just that, but soon learns things may not always go to plan...More than ten years after a disastrous battle, the war is still ongoing, and a girl with black hair and black markings washes up on shore...

In the midst of her first battle, Hinowa takes on the woman who killed her mother, Yomihime. Can Hinowa and her friends survive on the merciless battlefield? Then, a new and crazed general attacks from the Tenro Nation, and the warfare gets even fiercer...