Sasa Kurasaki serves as one of the main female protagonists at Aichi Symbiosis Academy and a key member of the Supreme Five Swords, the elite group enforcing strict rules across the student body. Renowned for her sharp tongue and ruthless personality, she frequently clashes with the male protagonist, Fudou Nomura. In combat, she wields a pair of flying guillotines with deadly precision, demonstrating significant strategic acumen and ranking among the academy's most formidable fighters. Her position grants her deep insight into the academy's hierarchical dynamics and the psychological conflicts between factions.

Her hardened demeanor originates from a troubled childhood marked by poverty, forcing her to fight for survival from a young age. This past humanizes her and fuels her fierce loyalty to the Supreme Five Swords. She exhibits traits consistent with the ISTJ personality type, relying on past experiences and factual analysis for decision-making, prioritizing logical and practical solutions, and maintaining a disciplined, organized approach. She often appears emotionally detached, displaying limited empathy. Her behavior also aligns with Enneagram Type 8, characterized by a need for control, assertive leadership, and a willingness to confront perceived injustice. She uses physical strength to assert dominance and protect those she deems vulnerable, though her methods can seem abrasive or aggressive. Her documented role remains confined to her interactions within the academy's power structure and her foundational backstory.