I'm Lily, but-!?" Lily, an apprentice nun who lives in a shabby monastery. On the way to the frontier alone to prepare for the winter in the monastery, he meets Cornelia, a beautiful marquis who is about to marry the marquis. They both decide to aim for the frontier territory, but they are caught up in an assault by bandits targeting her. Lily, who protected Cornelia, fainted-? Friendship, love, and survival...!? A misunderstanding love comedy begins with the replacement of the apprentice sister and the marquis!