Miyako lives in Room 202 of Hidamari Apartments, housing for Yamabuki Art High School students. Hailing from Fukuoka Prefecture, she comes from a large, financially strained rural family. This hardship necessitates significant sacrifices to fund her education, resulting in her occupying the cheapest apartment due to unrepaired damages like a leaky roof. Her limited means force an extremely frugal lifestyle; she often lacks funds for meals and wears hand-me-downs from older brothers, leading to a tomboyish look outside her uniform. She owns minimal possessions, lacking amenities like a TV, radio, or curtains until receiving donated ones.

Physically, Miyako has blonde hair, yellow eyes, and stands 165cm tall, making her the second-tallest main resident. Her hair is notably silky when maintained, though she typically wears it casually. Her demeanor is energetic and spontaneous, often perceived as ditzy or scatterbrained, driven by a childlike enthusiasm that sparks impulsive activities or sudden decisions. Despite this, she possesses a deeply compassionate core, consistently prioritizing her friends' comfort and well-being, especially Yuno's. Miyako played a pivotal role in helping Yuno overcome initial shyness upon moving in, and their bond remains intensely close, involving frequent shared baths, sleepovers, and playful teasing.

Miyako exhibits exceptional artistic talent, securing her admission to Yamabuki High via recommendation, likely with a full scholarship due to her family's finances. Her artistic style leans toward abstraction, reflecting a vivid imagination, and she maintains a broad appreciation for diverse art forms, including modern art, traditional styles, Japanese poetry, and folklore. Academically capable, she habitually downplays her successes, rarely seeking help or showing test papers. Beyond art, she demonstrates surprising skills: singing enka proficiently, excelling in physical activities like swimming, and performing improbable feats like constructing a pyramid of playing cards in complete darkness. Her sharp sensory perception and physical coordination allow her to master tasks like bicycle riding quickly.

Her development across the series involves subtle maturation while retaining core traits. As a senior later on, she mentors underclassmen Nori and Nazuna, showing increased emotional awareness and reliability. This growth balances her enduring playful nature, including her trademark teasing of Hiro about weight—a behavior stemming from either innocent observation or deliberate gadfly tendencies. Her family's finances improve during her senior year when her brother secures a lucrative farming contract, easing her path toward attending art college on scholarship.

During Sae and Hiro's graduation events, Miyako's supportive role is evident, particularly in comforting a distraught Yuno struggling with the seniors' departure, highlighting her empathy and deep investment in the friend group's stability. Personal quirks include sleeping nude without discomfort, observed during a group trip, and her symbolic association with a cat's paw motif—originating from an actual cat leaving a paw print on her stomach while sunbathing, representing her playful, mischievous qualities.

Miyako's narrative arc culminates in her continued residence at Hidamari Apartments after Sae and Hiro graduate, persisting in her artistic pursuits and maintaining her role as a supportive friend and senior figure within the evolving tenant community.