Kotori Itsuka is the foster younger sister of Shido Itsuka, a middle school student, and the commanding officer of the Ratatoskr organization’s airship Fraxinus. She is also secretly one of the Spirits, the fourth to have appeared in the story, though her powers were not initially revealed. Her personality is defined by a distinctive duality linked to the color of the ribbons she wears in her hair. With white ribbons, she adopts Imouto Mode, a gentle and affectionate demeanor that reflects her deep care and vulnerability. With black ribbons, she switches to Commander Mode, a sharp, authoritative, and occasionally harsh tsundere attitude suited to giving orders and making tactical decisions. This stark contrast allows her to be both a nurturing family member and a decisive leader. Her primary motivation is to protect Shido and to prevent catastrophic spacequakes by peacefully resolving conflicts with Spirits. Although she loves her brother dearly, she channels that affection into directing his dangerous missions and ensuring his safety from the command center.

Within Date A Live: Mayuri Judgement, Kotori plays a critical operational role. When a mysterious, invisible sphere called Kerubiel appears above Tengu City, it is the Fraxinus radar that detects it. Reine Murasame deduces that the sphere is composed of Spirit energy unconsciously emitted by Kotori and the other five sealed Spirits due to their strong feelings for Shido. As commander, Kotori helps organize and oversee a series of dates between Shido and each of the affected Spirits, including herself, to stabilize that energy. She monitors the spiritual readings, coordinates logistics, and remains deeply concerned for Shido’s well-being while maintaining her composed black-ribbon leadership. Her own date with Shido contributes directly to calming Kerubiel, and when the situation escalates into a battle against the rampaging Angel form of Kerubiel, she provides essential tactical oversight before joining the fight alongside the other Spirits. In the film’s climax, her sealed Spirit powers are temporarily unsealed, and she participates in the combined assault to rescue Mayuri and destroy the threat.

Kotori’s key relationships center on Shido, who is both her adoptive brother and the subject of her protective affections. She acts as his superior at Ratatoskr, giving him orders while still worrying over his safety. She also oversees the other Spirits living in the Itsuka household, fostering a sense of shared purpose and camaraderie. Through the larger narrative, she gradually learns to trust Shido’s methods more and to suppress her own aggressive Spirit instincts, showing growth in balancing her dual nature. Her development is marked by an increasing willingness to rely on others and to accept the risks of using her power only when truly necessary.

As a Spirit, Kotori commands intense fire-based abilities. She can transform into her Spirit form Efreet, wielding a halberd and manifesting an astral dress known as Elohim Gibor. Her flames are capable of immense destruction, potentially annihilating entire city sectors in seconds. However, prolonged use of this form risks unleashing a more violent, uncontrollable personality, so she treats her power as a last resort. Her Angel, Camael, further amplifies her combat capabilities. Off the battlefield, her greatest strength is her strategic mind; she directs complex operations, analyzes spirit energy fluctuations, and makes rapid tactical calls that shape the outcome of crises. These qualities make her both a formidable fighter and an indispensable coordinator in the events of Mayuri Judgement.