The story begins with the outbreak of war between the Kingdom of Ridgia and its neighbor, approximately six months after the protagonist, Verbena, lost her grandmother. Verbena, a low-ranking member of the Magic Division, is shocked by the war, as she has never experienced one before. Her colleagues, including Bob, who calls himself the "Black Fallen Angel," Jenkins, the "Spear of the Storm," and Princess Mizuryu, the "Princess of the Water Dragon," express their determination to fight. However, as the war intensifies, the Magic Division's upper ranks are progressively lost to Valhalla, leaving Verbena bewildered as to why they, who boasted so much, died before her. This leads to her unexpected appointment as the Magic Division Commander. Despite her grief and loneliness, Verbena resolves to fight to protect her kingdom and its people, finding solace in the belief that her loved ones are in Valhalla.
The narrative then shifts to the recapture of Norzak Castle, a territory lost to the enemy. While observing the enemy burning wheat fields from a hill, Verbena is approached by Gil, the Deputy Commander. Gil, a thirteen-year-old prodigy who broke the youngest admission record for the Magic Division, hesitates before confessing he has something personal to tell Verbena after the war. Verbena, who was Gil's instructor, fondly recalls their past interactions: rescuing him from enemy territory, catching fish for him, and him calling her "Master" before changing to "Verbena." Gil, now sixteen, expresses his desire for Verbena to listen to him after the war, stating he will no longer treat her as a child. Verbena agrees, unaware that this would be the last time she saw him. During the battle for Norzak Castle, Verbena is killed by an enemy mage, but manages to take many of them with her through a self-detonation spell, considering it a decent achievement for the "weakest commander." Her only regret is not hearing Gil's message.
The story then shifts to Gil's perspective. He met Verbena at thirteen when he joined the Magic Division. Orphaned and mistreated by his stepfamily, Gil discovered his magical abilities and, through self-study, passed the difficult entrance exam to escape his home. Verbena, with her short brown hair and ash-gray eyes, specialized in demolition magic and became his first true mentor. She provided him with research papers, took him on fieldwork, and encouraged him in magic competitions. Verbena also inadvertently caused an incident where Gil's abusive family was rendered bald, which Gil found immensely amusing. He grew attached to Verbena, finding joy in her company. However, as the war began, he witnessed Verbena's grief over fallen comrades, fueling his own sense of powerlessness. He admired her strength and sacrifice, but lamented that he couldn't protect her or express his love. He was unable to tell her he wanted to marry her, and now stands before her unmarked grave, reporting their victory.
Verbena's soul ascends to Valhalla, the divine hall for the brave, where she expects to reunite with her fallen comrades. However, upon arrival, she is met with anger from her former colleagues and her grandmother, Liza, the former Magic Division Commander and a legendary barrier mage. They are furious that Verbena used self-detonation magic, deeming it cowardly and a betrayal of her life. Despite her pleas, she is denied entry to Valhalla and is told she must be reborn to earn her place. Her grandmother, with great sadness, kicks her soul back to the mortal realm for a second chance at life.
Reborn as Aurelia Verbena Chilton, a noble daughter in the Kingdom of Ridgia, she retains her memories and her affinity for demolition magic. She dedicates herself to living a righteous life, often using her magic for practical purposes, such as preventing a flood by widening rivers and defeating a one-eyed bear. Her father, Ozwell, a former Major General, is initially exasperated by her destructive tendencies but eventually recognizes her potential and her desire to protect the people of their territory. Aurelia, driven by her past life's experiences and her grandmother's advice, focuses on making her territory prosperous. She proposes creating a large-scale carved Buddha (magai-butsu) on a cliff face, disguised as an ancient ruin, to attract tourists and boost the local economy. This project, involving her father, a priest, and a geologist, becomes a massive success, revitalizing the Chilton territory.
Later, Aurelia's explosive magic accidentally uncovers diamonds in a mine, leading to a diamond rush. However, this creates a labor shortage. When pirates attack the fishing port, Ozwell, now a Marquis, leads the charge with his soldiers, while Aurelia disables the pirates' firearms with her magic. The pirates are captured and sent to work in the mines, solving the labor shortage and improving security.
Meanwhile, Gil, now a thirty-two-year-old Magic Count and commander of the Magic Division, lives a solitary life, still mourning Verbena. He is pressured by Ozwell to marry Aurelia, partly because of her destructive magic, which would make her difficult to divorce, and partly to fulfill the noble duty of producing heirs. Despite his lingering feelings for Verbena, Gil agrees to the marriage, seeing it as a way to protect the honors and rewards that should have been Verbena's.
Aurelia, now sixteen, is surprised by the arranged marriage to Gil, whom she remembers as her subordinate. She finds him cold and distant, attributing it to the war's toll. Their wedding proceeds, with Aurelia's family and the people of Chilton territory bidding her farewell. As she prepares for her new life, Aurelia reflects on her second chance, embracing her family and her new identity, determined to live a fulfilling life and make her marriage to Gil a positive one, despite his emotional distance.
