Misa Kurobane, originally surnamed Kurobane, was the deceased older sister of Yusa Nishimori (born Kurobane). Her death resulted from a motorcycle accident at age sixteen, occurring roughly six months before the story's main events and preceding the series' beginning. Following her death, Misa's spirit persisted, interacting with the living world via her sister Yusa's supernatural Spiritism ability. This power enabled Misa to temporarily possess Yusa's body, an arrangement both sisters later voluntarily relinquished to Yuu Otosaka.

During these possessions, distinct physical changes manifested in Yusa's body: her eye shape sharpened, her eye color shifted from blue to red, and her blonde hair darkened to an orange shade matching Misa's original hair color seen in a photograph. Misa's natural eye color remains unspecified.

Misa exhibited a personality starkly contrasting with Yusa's, marked by tomboyish abrasiveness, a tendency for rash actions, coarse language, and a violent streak. She notably utilized her Pyrokinesis ability to threaten others. Historically recognized for physical prowess, Yusa recalled that "no boy in the neighborhood could win against her." Despite this harsh exterior, Misa demonstrated deep loyalty and affection, particularly toward her family. She harbored intense worry for Yusa's well-being and safety. This fierce protectiveness drove many actions during possessions, such as confronting individuals threatening Yusa. Her capacity for trust extended mainly to two friends who accepted her volatile behavior.

Misa's Pyrokinesis manifested solely during possession of Yusa's body, allowing her to generate and manipulate fire. She wielded this power defensively and for intimidation. During a confrontation with a television producer harassing Yusa, Misa burned obstacles to reach him, secured his agreement to cease harassment, and returned his incriminating phone.

Misa maintained a close bond with her sister Yusa, emphasized in a farewell letter stating, "I love you more than anything." She also sustained friendships with two individuals, one nicknamed Shō. Shō developed romantic feelings and confessed them while Misa possessed Yusa's body. Misa rejected his advances, urging him to "forget about me" and "live your own life," prioritizing his future happiness. She expressed gratitude toward both Shō and her other friend Kota before her departure.

Misa's character arc culminated in self-sacrifice. Recognizing the greater need to aid Yuu Otosaka's mission, Misa and Yusa willingly surrendered their abilities. This act removed her capacity to possess Yusa or interact physically with the world. Before separation, she left an emotional letter for Yusa expressing love, acceptance of her death, and a final farewell. Her spirit subsequently moved on.