Mikuru Shindo is the aunt and legal guardian of Chrono Shindo, the protagonist of the series. She is the younger sister of Chrono's father, Rive Shindo. A young woman with orange hair and blue eyes, she works as the CEO of a cosmetics company and is responsible for raising Chrono after his parents' absence. Mikuru is cautious by nature, especially toward individuals she considers reckless, such as Shinemon Nitta, whom she knew from school. Her primary motivation is to provide a stable, supportive home for Chrono and to keep him safe from harm. She acts as a parental figure throughout the story, appearing at key moments to offer encouragement or express concern for Chrono's well-being. Her relationships are centered on her family: she maintains contact with her brother Rive through phone calls, and she has a history with Shin Nitta as a former schoolmate. While not a cardfighter herself, her role is to anchor Chrono emotionally and to witness his growth as a fighter. Over the course of the narrative, she becomes more directly involved in the events surrounding Chrono, showing her protective nature and her willingness to support him even when facing dangerous opponents. Her notable abilities lie not in combat but in her steady, caring presence and her success as a businesswoman.