A student from class 3-3, Miyauchi is a skilled karate master, as her family owns a dojo. She is very intimidating, brave, confident, and dangerous. She claims to have had masters that defeated buffaloes and bears, and can be recognized for the honor of killing Argentavis. Though she is very insectophobic, shivering, screaming, even crying at the sight of insects.
She is a childhood friend of Zaji.