Thirteen-year-old middle school student Tokio Meguru finds her ordinary life abruptly disrupted when she collides with an eighteen-year-old woman sharing her name, Meguru. This older namesake, possessing a passionate and driven personality contrasting sharply with Tokio's conventional demeanor, is fleeing a mysterious organization. Their unexpected encounter and shared name forge a narrative link between them.

This meeting forcibly pulls Tokio into the older Meguru's struggle against her pursuers. Tokio's involvement stems not from choice but from the circumstances of their collision. The dynamic between the two centers on their differing approaches to the conflict, juxtaposing the older Meguru's assertiveness against Tokio's initial lack of involvement in such confrontations.