kusakabe rei, irido mizuto, irido yume, mamahaha no tsurego ga moto kano datta, commentary request, second-party source, translation request, !?, 1boy, 1girl, black hair, blush, book, brother and sister, brown eyes, closed mouth, collared shirt, green jacket, hair between eyes, hair ornament, hairclip, holding, holding book, jacket, open book, open clothes, open jacket, reading, shirt, siblings, simple background, spoken interrobang, step-siblings, twirling hair, upper body, white background, white shirt