Makina Irisu is a petite girl with a youthful, childlike appearance that contrasts with her actual age. She has light brown hair styled in twin pigtails, each tied with a blue ribbon. Her eyes are large and expressive, often conveying a wide-eyed, innocent look that reflects her eccentric personality.

She is typically seen wearing knee-high socks of mismatched colors, adding to her quirky visual identity. Makina has a small chest, which she often attempts to exaggerate by puffing it out in a comical effort to appear more mature.

Makina Irisu is initially very shy and withdrawn, especially around people she is not familiar with. Her introverted behavior stems from a deep fear of rejection, causing her to avoid others to prevent being disliked. However, once she becomes comfortable with someone, she reveals her energetic and playful side, often behaving in a lively and childlike manner. She also has a distinctive verbal tic, frequently ending her sentences with the phrase “noyosa.”

After forming a bond with Yuuji Kazami, Makina becomes noticeably more outgoing and confident. She begins to imitate his disciplined demeanor, occasionally acting like a miniature drill sergeant in both speech and mannerisms. Alongside Sachi Komine, she adopts some of Yuuji’s habits, including a more commanding tone and cold expressions, often played for comedic effect. She also trains in basic self-defense under Yuuji’s guidance.

Makina spends much of her time in Amane Suou’s room, frequently relying on her for meals and affection. She enjoys teasing her classmates particularly Michiru Matsushima and often engages in light-hearted antics around the dorm. Despite her unusual behavior, Makina gradually becomes well-liked by the other students and eventually manages to get along with all of her classmates, including Yumiko Sakaki.

Makina Irisu was once considered a prodigious child, admired for her intelligence and potential. However, her life took a tragic turn eight years prior to Yuuji Kazami’s transfer to Mihama Academy. During that time, her father, Masataka Irisu, uncovered political corruption within the influential Irisu family. In response, Makina was kidnapped, and a ransom note was sent to Masataka.

Masataka attempted to deliver the ransom personally, but was fatally shot in front of Makina. The responsibility of managing the crisis was passed to the Irisu branch family, who used the incident as an opportunity to sideline Makina. Rather than rescuing her, they abandoned her at the scene.

Makina remained tied up beside her father’s corpse for six days before being discovered and rescued. The psychological trauma left her in a near-catatonic state. It took three years before she could respond to basic questions, two more before she could form coherent thoughts, and an additional year before she was able to express normal emotions again.

To ensure she would not become the successor of the Irisu family, the branch family faked her continued hospitalization and secretly enrolled her at Mihama Academy. This allowed her younger half-sister, Sarina Irisu, to be designated as the next family heir.

• Yuuji Kazami: Makina initially maintained a distant relationship with Yuuji, but began to open up after he shared a story about how crawfish can turn blue an odd yet memorable moment that sparked her affection toward him. Over time, she became deeply attached to Yuuji and began mimicking his straightforward, confident manner of speech. This change in demeanor helped her improve her communication with others, particularly Amane Suou. In both the anime and her visual novel route, Makina admires Yuuji to the extent that she bribes him into becoming her “papa.” Although confused at first, Yuuji accepts her request, forming a unique pseudo father-daughter bond. Makina is notably brave and selfless when it comes to protecting Yuuji, often showing the most resolve among the Mihama girls. In her visual novel route, their bond becomes romantic, and she seeks intimacy with him, especially when she senses he is under stress.

• Yumiko Sakaki: Makina and Yumiko had a distant relationship at first, largely due to Yumiko’s cold and guarded nature. However, after Yuuji helps Yumiko confront her trauma, Makina begins to engage with her more openly. Despite Yumiko’s serious personality and occasional aggression, Makina frequently teases her sometimes provoking Yumiko’s sharp form of retaliation, but always with playful intent.

• Amane Suou: Makina shares a deep, almost familial relationship with Amane, often described as that of a daughter and mother. Despite having her own room, Makina frequently sleeps in Amane’s, and Amane often takes on a nurturing role in her life. It is implied that Makina may have gravitated toward Amane for maternal comfort, possibly due to her strained relationship with her biological mother.

• Michiru Matsushima: Makina enjoys teasing Michiru, often playing off Michiru’s exaggerated tsundere personality and perceived naivety. Their interactions are typically lighthearted, with Makina frequently poking fun at Michiru’s behavior and lack of self-awareness.

• Sachi Komine: Makina and Sachi share a number of common interests, including their love for the fictional superhero series Tuna Man though each favors a different character. They also enjoy watching television together and often bond over their shared experiences as the youngest girls at Mihama Academy. Their similar sense of humor and childlike enthusiasm allows them to connect easily.

The given name Makina (蒔菜) is composed of the kanji 蒔 (maki), meaning “sow” (as in sowing seeds), and 菜 (na), meaning “vegetables” or “greens.” Together, the name can be interpreted as “one who sows vegetables,” or more broadly as a reference to nature and growth. In some interpretations, it can also refer to fennel or simply “vegetable.”

Her surname, Irisu (入巣), consists of 入 (iri), meaning “entering,” and 巣 (su), meaning “nest.” The name may evoke the image of entering a home or safe space, which contrasts sharply with her traumatic childhood and isolation from her family.