Risha, the reclusive heir to the Odessey family, is framed as a villainous noblewoman in a plot by Countess Tokia to seize her family's lands. As punishment for an alleged assault, Risha is locked inside a stable that is then set on fire by Tokia's allies. Just as she accepts her impending death, a strange voice speaks in her mind. The voice belongs to Oda Nobunaga, the legendary warlord from another world, who chooses this moment to possess her body.

After surviving the fire, Risha wakes to discover she can now see and hear Nobunaga, though he remains invisible to everyone else. Her quiet and timid personality clashes violently with Nobunaga's bold, strategic, and impulsive nature. While Risha simply wants to live peacefully and avoid further conflict, Nobunaga sees every social situation and political maneuver as a battlefield to be conquered, pushing her into increasingly daring actions.

The story takes place in a noble society centered around the Royal Academy, where family politics, engagements, and social standing are matters of life and death. Risha must balance her own fearful nature with Nobunaga's relentless drive to unify everything under his control, even as she insists she has no desire to conquer the world. The manga was written by Yoshiro Yotsuha, known for Paripi Komei, with art by popopo and original character designs by Haruno Hisaku.

As the series progresses, Risha grows closer to a young man named Ranmeil, though her inexperience with normal relationships leaves her flustered by his attention. When news arrives that war has broken out between the Sazanbek and Tokia families, Risha is deeply pained but must find the resolve to move forward. As the end of the school year approaches, she succeeds in inviting a mysterious swordsman named Weval to be her partner at the graduation party. Weval's true identity turns out to be someone of far greater importance than anyone expected.

At the graduation party, Risha faces off against Octavia, a noblewoman who holds a grudge against her. With Nobunaga's bold strategies and clever tactics guiding her from within, the once-timid young lady turns the party into a stage for a dramatic reversal of fortune. By the series conclusion, the pair bound by their strange destiny reach the end of their journey together, with the fool young lady overturning her fate entirely. The complete series spans three volumes.