"Hitokiri" Shoujo, Koushaku Reijou no Goei ni Naru

Shurine is a girl who has mastered the sword, having been raised to serve as a bodyguard. However, she is falsely accused of assassinating the person she is guarding and forced to goes on the run. Driven from her home, Shurine meets Lutecia, a duke's daughter whose life is in danger after being caught up in a battle over royal succession.