Toko Aoki is a high school student and pottery club member in Tajimi City. She has waist-length black hair, usually worn with a light-blue headband, and black eyes. Her surname combines "blue/green" and "tree/wood," her given name "ten" and "child."

Toko's family has deep roots in Tajimi's pottery traditions. Her grandfather, a highly respected expert in the local community with exacting standards, initially creates pressure for her. Feeling judged by his expectations, especially as he serves as a competition judge, Toko begins her pottery journey focused on technical precision and traditional methods, often using shades of blue.

A turning point occurs when Toko creates a bright orange bowl for a cultural festival exhibition, departing from her usual style. Unbeknownst to her, her grandfather visits and is profoundly moved by this piece, recognizing it as a bold expression of her individuality. This leads to reconciliation; Toko learns her grandfather's critiques aimed to ensure she mastered foundational skills, freeing her to develop her unique artistic voice. He explicitly expresses pride in her new direction.

This experience positions Toko to support Himeno Toyokawa, who faces parallel pressures related to her late mother's pottery legacy. Toko shares her own story of overcoming expectations, emphasizing personal expression in art. Her guidance helps Himeno embrace experimentation over perfection. Toko also interacts with Arai Kentarō, an actor and former apprentice of her grandfather, during the festival, further bridging the generational gap in her family's legacy.

Through her narrative, Toko evolves from replicating established forms to valuing innovation within her craft, symbolizing the balance between honoring tradition and pursuing individual creativity.