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.

As Lutecia is being attacked by an assassin, Shurine makes her an offer, "I'm a bit short on money. If you need a bodyguard, I'm available right now."

Their encounter will determine the fate of the kingdom! A girls-love swordplay battle fantasy begins!