In modern-day Japan, 13-year-old Hajime Yasaka relocates to the countryside to live with his grandfather. En route to his new home, a disoriented Hajime stumbles upon a cafe named Ark, where he instantly falls for one of the waitresses: the stunning Sayoko "Arashi" Arashiyama. Although Arashi is initially indifferent to the boy, her demeanor shifts rapidly after she takes Hajime's hand, causing her to believe they are "connected." It turns out that Arashi is far from an ordinary teenager—in truth, she is the ghost of a girl who died in World War II. By touching a man she connects with, she acquires the power to travel back in time. Thrilled to have found someone capable of activating her abilities, Arashi asks Hajime to assist in her mission: to rescue civilians from the war's devastation that took her life. Smitten with Arashi, Hajime readily consents. However, as the pair delve deeper into Arashi's past, they soon realize that she is not the only one capable of transcending time.