Daegonggaui Saeaganeun Jogeum Sanawoyo

Special Forces captain Yunseo Jeong dies during a training exercise and opens her eyes as Rudia, a five-year-old side character in a fantasy novel whose story ends badly. Because she already knows how the plot unfolds, she slips away from an avaricious uncle and takes shelter with the household of a formidable Archduke. Rewriting what comes next proves harder than expected, with an unwilling fiance, a spiteful beastman, and a prince fated to be her killer all in the way. Her military training may be the only tool she has against her scripted end.