Thirteen-year-old Kokone lives on a remote, insular island where she feels trapped. Her only escape is visiting the small local airfield with a mysterious high school boy she calls Hi-kun, who shares her love of airplanes. He tells her that the blue planes will one day carry them away, and together they dream of their futures: he wants to become an aircraft mechanic, and she, inspired by the ground crews she watches, develops a desire to work in ground handling. Then Hi-kun suddenly vanishes without explanation. A decade later, Kokone has fulfilled her side of that promise and works as a ground handler, or grahan, at Haneda Airport, where her duties include guiding aircraft, handling luggage, and operating ground equipment to ensure safe and on-time departures. Her first days on the job are marked by mistakes and unexpected challenges, but she is determined to grow into a competent professional. At the airport, she crosses paths with the taciturn but dedicated pilot Matsunaga, toward whom she begins to develop romantic feelings, and she also grows close to her cheerful senior colleague Tomori, whose hidden past eventually comes to light. A love triangle begins to form as Kokone navigates her emotions while striving to prove herself at work. The story follows her efforts to master her trade, her deepening connection with Matsunaga, and the complications that arise when a marriage meeting is proposed between Matsunaga and a trusted cabin attendant named Izumi. Key narrative arcs include Kokone being assigned to ride along on a flight piloted by Matsunaga as a symbolic guardian, the revelation of Matsunagas own complicated history, and the looming rumor that Tomori may leave the job. Through workplace struggles and personal entanglements, Kokone reaffirms her commitment to becoming a fully capable ground handler, all set against the meticulously researched backdrop of real ANA airport operations.