Tamaki Kasuga travels to Kifumura, believing she'll live with her grandmother, only to learn she's the next 'Tamayori princess' tasked with sealing the sword Onikirimaru. She's assigned male guardians from another family to protect her.

Believing she is to live with her grandmother because her parents are transferred abroad, Tamaki Kasuga travels to the town of Kifumura. There, she is told that she is actually to perform the role of sealing the sword Onikirimaru as the next 'Tamayori princess'. To protect her, she is also assigned young men from another family as guardians.—Mattias1