She cherishes humans. As a teacher and guardian who protects the history of the Human Village, she is very favorable toward humans and possesses strong maternal instincts. Being a half-beast, she values the coexistence of humans and youkai and works hard to achieve it. She places great importance on etiquette and dislikes rude people; one might even be disliked by her for failing to greet her. When a threat to the Human Village appears, she uses her ability to hide history to protect the village. She possesses the ability to hide history, 'eating' the history of a specific target so that others cannot perceive it. While it is the ability to hide history, it differs slightly from reality manipulation that makes things as if they never happened. Even if the records of history disappear, the memories of the people related to that history are not completely erased. She wears a blue dress with short white sleeves that shows a bit of cleavage. A red ribbon is tied below the collar. Her hat is a unique building-shaped one engraved with ancient characters and a red ribbon. She has long blue hair and a voluptuous chest and hips despite her small stature. She wears platform shoes because she is a bit self-conscious about her height. If students don't do the homework she assigns, they get a harsh scolding, and in severe cases, she uses a headbutt. She is a teacher at the village school, but her lessons are often unpopular because the content is abstruse and boring. She records history whenever she has a break from teaching. She uses a stiff tone with those she dislikes or, conversely, those she is very close to, but usually speaks in a normal, feminine manner. She exudes an intellectual and elegant atmosphere, and in her human form, she radiates intellectual charm with neat clothing and a calm expression. This blends with her profession as a history teacher to create a graceful aura. Contrary to this appearance, she happened to discover and fall in love with the concept of magical girls. She secretly collects magical girl merchandise, sews her own costumes, and has even come up with a name for her transformed self (Magical Girl Luna☆Keine) which she uses every night away from Mokou and others. She has been active in her blue magical girl outfit, practicing poses for quite some time (she is too embarrassed to let anyone find out and records her activities in a notebook). She carries a magical wand when 'transformed' (it seems she carries it for physical striking rather than using magic. Sometimes she uses it for dramatic effect when erasing someone's memory). She secretly likes Mokou and wants to dress her up in a magical girl outfit to fight alongside her. She hopes to help people in her magical girl form someday, though she is still embarrassed to show this side to others. She feels a bit of shame that she is doing such things, even as she gets used to it. Her ultimate move as a magical girl is also a headbutt. History is a record of important events, distinct from ordinary daily life. Depending on how history is recorded, the truth can go missing. However, even if history is recorded incorrectly, the facts do not completely disappear. The ability to hide history is a manifestation of this nature of history.

This is Keine's form when she transforms into a Hakutaku. Her clothes remain the same shape but change to a light green color, and she gains long light green hair, two bull horns, and a long light green tail. She only turns into a Hakutaku during a full moon. When transformed, she becomes extremely sensitive and irritable. However, since Keine's original personality remains, she isn't that dangerous. No villagers have seen or know about this form. Occasionally, she even carries out her magical girl activities at night in this state.

She is chic and cold-headed but kind and strong. However, she carries many emotional wounds and is blunt and quiet because she doesn't interact much with humans. Surprisingly, she is shy and deeply caring. She uses masculine speech and behavior. Since Keine is her only friend, they often hang out together, and she helps clean Keine's school. She lives alone in a hut in the Bamboo Forest of Lost. She harbors a deep hatred for her nemesis, Kaguya (who lives in Eientei in the bamboo forest), and they are in a relationship of killing each other repeatedly. She has long white hair tied with charms. She wears a white t-shirt and red overalls. She has large hips, which are emphasized by how tightly she wears her overalls. She has a red and white ribbon on the top of her head. She guides humans lost in the bamboo forest or protects them from youkai, but avoids forming relationships beyond what is necessary. She is unaware of Keine's hobby (magical girls). Having lived for a long time, she has mastered fire manipulation techniques and maximizes her power by burning her own life force using her immortal body.