Anju L. Narumi, commonly referred to as Narumi-sensei, is a teacher at Alice Academy who serves as the homeroom instructor for the Elementary Division's Class B and also teaches Japanese. He is a former Special Alice Star student, indicating that during his own time at the academy he was a highly accomplished Alice user. His background includes having been a student alongside Yuka Azumi and Izumi Yukihira, a connection that becomes deeply significant later in the story. He harbors unresolved feelings for Yuka Azumi, who is the mother of Mikan Sakura, the protagonist, and he later allows Mikan to call him "Dad." This history of unrequited love and the tragic fates of his former classmates fuel a sense of guilt that partly motivates his protective behavior.

In terms of personality, Narumi-sensei presents an outwardly cheerful, funny, and somewhat eccentric demeanor. He has a noticeable habit of dressing in flamboyant and strange outfits, and he often devises unusual ideas for school plays that reflect his creative and theatrical side. Despite this lighthearted exterior, he is also a deeply caring individual who genuinely loves his students and wants to protect them. He is frequently absent from his own classroom, leaving the substitute teacher Fukutan in charge, which leads to a reputation as a negligent teacher. Yet when a student is in danger, he steps in decisively and without hesitation. His personality is described as having a hidden colder edge beneath the surface, a result of the stress accumulated from wielding a powerful pheromone ability from a young age, which shaped him into someone who learned to hide his true feelings behind a comedic facade.

His motivations are rooted in both his affection for his students and his unresolved past. He seeks to protect the children under his care, particularly Mikan Sakura, whom he treats as a surrogate daughter. He is also motivated by a desire to oppose the corrupt administration of the academy, a goal he pursues covertly alongside other like-minded faculty members such as Misaki-sensei. His personal guilt over failing to protect Yuka Azumi and Izumi Yukihira drives him to take a more active role in resisting the academy's darker practices.

Narumi-sensei plays a multifaceted role in the story. He is the teacher who first encounters Mikan when she arrives at the academy and helps her gain enrollment. He acts as a mediator between the students and the school's authority figures, often dealing with disruptive behavior from Natsume Hyuuga when the latter attempts to break rules or escape. He also serves as the moderating teacher for the Somatic Ability users, a class that includes students with physical or bodily-type Alices. Beyond his classroom duties, he is a key figure in the underground resistance against the academy's principal and the Z organization, using his position to gather information and protect students from the institution's more sinister operations.

His key relationships include his close friendship with Misaki-sensei, despite their frequent bickering and Misaki often scolding him for stealing bean whips from her greenhouse. They have known each other since childhood, as shown in an album of old photographs. He shares a paternal bond with Mikan Sakura, allowing her to call him "Dad" and looking after her as a living connection to his lost love, Yuka Azumi. He also maintains a complex professional relationship with Natsume, whom he often has to discipline, and a cooperative alliance with other faculty members who oppose the administration. His past relationship with Yuka Azumi is one of unrequited love that continues to shape his actions, and he later interacts with her again when she returns as a member of Z and steals his Alice, though his power proves inexhaustible.

Throughout the series, Narumi-sensei undergoes significant development. Initially presented as a comedic and unreliable teacher, his character deepens as his past is gradually revealed. The story explores his history as a student, his love for Yuka, and the guilt he carries. He transitions from a passive figure who avoids responsibility into an active protector and a key player in the rebellion against the academy. His willingness to sacrifice and his determination to safeguard his students become central to his role, and he emerges as a figure of quiet strength and loyalty.

His notable ability is the Human Inclination Pheromone Alice, a somatic-type power that allows him to emit pheromones that can charm and influence older individuals and cause younger children to faint. This ability suits his personality and is described as being as beautiful as the universe in its expression. He uses it in a generally ethical manner to guide his students and protect them, though it can also be used as a form of discipline when necessary. His Alice is classified as a Somatic Ability, and its power is formidable enough that even when stolen by Yuka, it continues to emanate from him endlessly, demonstrating its depth and his mastery.