Kashiwada is a junior high school student, 13 at the start and turning 14. She has white hair and purple eyes. Her face maintains a completely unchanging, blank expression regardless of circumstances, with no visible shifts in her eyes or mouth. Subtle blushing sometimes hints at her internal emotions. She typically wears her school uniform: a white long-sleeved shirt with blue accessories and a blue skirt.

Incapable of showing emotions facially despite feeling them internally, Kashiwada is fundamentally shy, especially around Oota, often needing courage for simple acts like handing him items. She is bluntly honest, openly stating her feelings when asked or when necessary. This directness, combined with her expressionless face, frequently leads others to misinterpret her emotions; only Odajima consistently understands her. She exhibits low physical proficiency, startles easily, runs in an unusual T-pose posture, and expresses preferences for beans, small enclosed spaces, and Oota.

Her relationship with Oota develops significantly. He repeatedly tries to provoke visible emotional reactions through pranks and scares, attempts that fail due to her unchanging expression. Drawn to his highly expressive nature contrasting with her inexpressiveness, she frequently observes him. Their interactions evolve into mutual romantic feelings, though Kashiwada struggles with shyness in expressing affection. Classmates observe their unique dynamic with interest, often commenting on Oota's new schemes. The story explores whether their opposing natures can sustain an attraction.