"Raise de Kekkon shite kuremasu ka" to Chikatta Buka ga, Gense de wa Toshiue no Kishi Danchou-sama ni Natte Ite, Hontou ni Kekkon wo Semararete Iru Ken

Livia, a young woman, is plagued by nightmares from a female soldier's point of view, where she loses her subordinates before her eyes. Then one day, at a party held at the royal palace, she is suddenly called out. The moment she saw the beautiful Knight Commander, Claudio, Livia's memories of her previous life come back to her.
Livia and Claudio's previous lives were that of a female soldier and her subordinate, whom Livia pledged to marry in her next life upon her deathbed! In the meantime, Claudio immediately proposes to Livia!