Shiroha Naruse is a 17-year-old resident of the isolated Torishirojima, distinguished by her white hair, blue eyes, and 155 cm stature. She lives solely with her grandfather, Kobato Naruse, following her father's accidental death and her mother's subsequent disappearance. These losses led to profound social isolation; prior to the story, her grandfather was her only companion. Years of seclusion fostered social awkwardness, manifesting in blunt speech that often disregards others' feelings. Shiroha possesses precognitive abilities. A traumatic incident occurred when she warned a boy about a foreseen drowning, which he misinterpreted as a curse. After he nearly drowned, rumors accused Shiroha of pushing him, resulting in police interrogation. Though cleared, the experience instilled a deep fear that her powers could cause harm, strengthening her withdrawal. Her visions later include foreseeing her own death by drowning during a summer festival and, in an alternate future, her death during childbirth. Her development focuses on overcoming isolation. Initially distant, using phrases like "You should probably not bother with me," she gradually opens up to the outsider protagonist. Connections with others reveal hidden traits: a love for shonen manga, a competitive spirit (especially in table tennis), and preparedness exemplified by carrying portable cooking utensils. She enjoys cooking, fishing, and watermelon ice candy. Significant temporal elements shape Shiroha's narrative. In one future, she marries the protagonist and becomes pregnant. Exhausted by efforts to prevent her daughter Umi from inheriting her powers, she dies in childbirth. Umi then travels back to 2000, initiating events to alter this outcome. Shiroha's route concludes with Umi's interventions erasing the tragic future, enabling Shiroha's survival and the reclamation of her summer experiences. Relationships include a childhood connection to Ao Sorakado's group, though she initially denies closeness. She inadvertently uses affectionate language for Ao and considers herself an older sister figure to Miki Nomura. The story explores her complex bond with the protagonist, evolving from reluctance to deep emotional reliance, ultimately changing both their destinies.