Motoko Iura is Shuu Iura's younger sister and a middle school student with green hair, olive eyes, and standing approximately 1.50 meters tall. Her birthday is May 14. She lives with her brother; their relationship is characterized by frequent bickering and mutual teasing, masking a deep mutual care. Generally quiet, Motoko is easily annoyed, especially by Shuu's loud personality. Academically diligent, Motoko faces declining grades. This causes her significant distress as she fears failing to gain admission to her desired high school. Overwhelmed by her efforts not yielding results, she experiences an emotional breakdown. Shuu responds supportively, even offering to confront a teacher who laughed at her aspirations. To address her studies, Shuu arranges for Kyouko Hori to tutor Motoko until her exams conclude. This tutoring involves additional support from Hori's social circle, including Miyamura and Souta. Motoko's core motivation is academic achievement, driven by a fear of disappointing others and a desire for validation. Her anxieties lead to comparisons with peers like Hori and Miyamura, reflecting underlying insecurities despite persistent effort. The siblings' relationship evolves to reveal deeper mutual reliance. During an emotionally charged exchange, Motoko states, "I don’t want you to hate me," a sentiment Shuu echoes. This moment underscores the bond beneath their contentious interactions, highlighting their protectiveness and shared vulnerability.