Misao first appears as a tutor employed by the evil organization DARK, responsible for educating Hiroshi Kubo, the older son of Professor Gill. When the android Kikaider destroys DARK, Misao and Hiroshi are left homeless. Forced to survive on the streets, she turns to pickpocketing but follows a strict personal code: she only steals from the wealthy or the wicked, never from the innocent or the poor. This principle reveals a latent sense of justice beneath her desperate circumstances.

After the death of Rieko, the guardian of Hiroshi’s younger brother Akira, Misao assumes the role of caretaker for both boys. She becomes their protector and parental figure, guiding them through the dangers posed by the new organization SHADOW and its robotic enforcers. Her relationship with Hiroshi is particularly close, as she has been with him since before DARK’s fall, and she shows the same devoted concern for Akira.

Misao’s personality is pragmatic and resilient. She does not possess superhuman abilities; her strengths lie in her resourcefulness, streetwise cunning, and unwavering loyalty to the children under her care. Over the course of the series, she grows from a desperate survivor into a determined guardian, willing to face danger to keep Hiroshi and Akira safe. Her development underscores the human cost of the ongoing conflict between androids and evil organizations, grounding the story in a personal, emotional struggle.