Natsuki Kamikawa is a middle school student attending Musashi Tama Middle School in Tokyo. In the real world, she is a victim of relentless bullying by her classmates, which drives her into a deep emotional isolation. To escape her suffering, she inadvertently enters the dream world after attempting suicide, becoming a witch known as the Witch of Solitary Shadow. A devoted fan of the anime Onmyo Ukiyo Ayakashi-Barai, she initially embraces her dream existence by transforming into an onmyodo mage, using her newfound abilities to curse and retaliate against her bullies. This fantasy gives her a sense of power and control that she lacks in her daily life, and she revels in the role of a heroic fighter. However, she eventually grows bored with the repetitive nature of her dream adventures, realizing that even in this world her story feels stagnant.

Her personality is defined by a longing for escape and a desire for justice against those who torment her, but she also displays a capacity for self-reflection and growth. When Haruto Tsukishiro, the main protagonist, and the researcher Kanzaki encounter her in the dream world, she is actively using her witch powers to harass her bullies. Haruto attempts to persuade her to confront her real-life problems rather than hide in fantasy. Their interaction leads to an elaborate shared dream where aliens are invading, and Natsuki and Haruto pilot a giant robot together to fight the threat. This collaborative experience helps Natsuki recognize that she can face her real-world struggles directly. She ultimately decides to leave the dream world and return to reality, showing a newfound resolve to address the bullying. In a subtle twist, the bullies subsequently begin receiving abusive messages on their phones, implying that Natsuki may have turned the situation around.

Natsuki’s role in the story is that of a supporting character appearing in the sixth episode, representing the theme of using dreams as a refuge from pain. Her key relationships include her adversarial connection with her bullies and her transformative bond with Haruto, who acts as a catalyst for her personal change. She later appears alongside other awakened witches in the series’ finale, indicating that she has become part of a larger network of individuals who have confronted their inner demons. Her notable abilities in the dream realm include onmyoji magic that allows her to curse others and the capacity to pilot a giant robot during the alien-invasion scenario. As the Witch of Solitary Shadow, she embodies the loneliness and shadow of bullying that isolate individuals, but her arc demonstrates the possibility of moving from victimhood toward agency and self-determination.