Nico Hirata is a relatively tall, slender vampire with distinctive red hair, typically styled partially in a bun or loose and consistently covering the left side of her face. Her notable features include yellow eyes, earrings on each ear, and sharp teeth that become fully visible when she becomes angry or volatile. She typically wears a dark suit with a plain white shirt and matching pants, paired with high heels and no socks, though she has worn a simple white top and short skirt for occasions like Halloween. She serves as the leader of the Vampire Council and works as a night school teacher. Personality-wise, Nico presents as level-headed and dignified, often acting as her clique's representative. She enjoys discussing romance topics, has a fondness for alcohol, and expresses disdain for lewd subjects. She takes pride in her popularity and engages in friendly competition with other female vampires. Despite her calm demeanor, a violent side emerges when highly upset, leading her to consider or commit killing if sufficiently provoked; she generally avoids it and does not derive pleasure from it. Fundamentally supportive and forgiving, she held no resentment toward Anko Uguisu after being shot in the head. She actively aids Kou Yamori and Nazuna Nanakusa and shows genuine care for students like Lira Echigo. Nico enjoys admiration from male students, rejecting their advances while young but appreciating it when they return years later as mature adults. Her vampiric abilities include immortality, levitation, phasing through objects, superhuman speed, durability, strength, supernatural charm, and accelerated wound regeneration. As Vampire Council leader, she strategizes to manage human knowledge of vampires, initially pressuring Kou to turn to prevent him spreading awareness. She commands five familiars and views creating vampire families and descendants as vampirism's core purpose. She maintains close friendships with fellow vampires Kabura Honda, Seri Kikiyou, Midori Kohakobe, and Hatsuka Suzushiro. Nico has mentored individuals including Nazuna Nanakusa and Kyouko Mejiro, the latter having once attempted to kill her. Her relationship with Kou evolved from initial wariness to supportive mentorship. Her background includes teaching night classes, interacting with humans and vampires. Her name is speculated to derive from an anagram related to Japanese spring herbs like nipplewort or koonitabirako. Key interactions highlight her traits, such as a dismissive remark to Nazuna and Anko about understanding unpopularity, reflecting her pride. Her forgiveness of Anko underscores her empathy and lack of grudges. Her development consistently reinforces her role as a stabilizing force within her group, balancing her dignified public persona with vulnerability and protective instinct.