TV-Series
Description
Akitsu is a Sekirei known as a discarded or scrapped number, which places her in a unique and unfortunate position within the Sekirei Plan. Her designation as a scrap number is the defining fact of her existence and shapes every aspect of her character. Originally, she was Sekirei No. 07, a high-powered single number, but a failed adjustment procedure performed by an inexperienced researcher left her with a permanent red Sekirei crest on her forehead, rather than the standard placement on the back. This incident rendered her unable to undergo the "winging" process with an Ashikabi, meaning she cannot form the standard bond that powers most Sekirei and allows them to use their full abilities, such as the Norito. Because of this failure, she was deemed useless by the disciplinary corporation MBI and marked for disposal.

Akitsu’s personality is a direct reflection of her power and her tragic past. She has a cold, melancholic, and almost emotionless demeanor, speaking very little and usually in a flat, neutral tone. This icy exterior masks a deep-seated fear of being abandoned and thrown away, a terror born from her experience of being rejected by the very people who created her. As a result, she is fiercely loyal and submissive to any master who will accept her, following orders without hesitation to prove her worth and secure her place. Despite her usual composure, she is capable of showing deep emotion when her "ice melts," such as blushing or crying when expressing her feelings. She also displays a quirky absent-mindedness on rare occasions, most notably once entering a battle without wearing underwear, not out of defiance but simply because she forgot. She is also shown to be envious of other Sekirei like Homura, who still have the potential to find an Ashikabi and be winged, something she believed she could never experience.

Akitsu’s primary motivation is to find a place where she belongs and to avoid being cast aside. This need for acceptance is fulfilled by Hayato Mikogami, the Ashikabi of the South, who found her after she fled from MBI. Even though she cannot formally wing with him, she considers him her master and serves him with absolute devotion. Her role in the story is as one of his primary enforcers, acting as a powerful combatant in the battles of the Sekirei Plan. Her most significant relationship is with Hayato, and her greatest desire is to be useful to him so that he will not discard her as MBI did. She also has a notable rivalry with Homura, a fire-wielding Sekirei. Their elements are natural opposites, and they have fought multiple times to a stalemate, with Homura acknowledging her incredible strength and theorizing that her immense power was the real reason she was scrapped, as she was too dangerous to be left unregulated.

Akitsu’s development is the most significant aspect of her story arc. For much of the narrative, she is defined by her inability to be winged, but this changes during the battles on Kamikura Island. Facing a desperate situation, her deep bond with Hayato finally triggers her emergence, and she successfully undergoes the winging process, her forehead crest disappearing as she gains the ability to use a Norito. Overjoyed to finally have her wish fulfilled, she professes her love for Hayato and gains access to her true power. However, the release of this fully-powered Norito is so immense that it pushes her to the point of self-termination. Shortly after achieving her dream, she dies from the strain of using her abilities to protect her Ashikabi and his other Sekirei. Her death is not permanent, as she is later revived by the plant-controlling Sekirei Kusano, allowing her to continue fighting by Hayato's side in the final conflicts.

Akitsu’s notable abilities are centered on the manipulation of ice, a power that makes her one of the most formidable fighters in the series. Her control is highly refined, allowing her to instantly freeze targets within her line of sight, such as an opponent's limb. She can launch projectiles of jagged ice, such as in her attacks Flying Icicle and Icicle Snow Storm, to pierce enemies from a distance, and can also create barriers for defense. Even before being winged, her raw power was enough to fight on par with Homura, one of the strongest Sekirei, and she possesses great speed, agility, and tactical judgment, as shown when she immediately retreated from a fight against the far more dangerous Karasuba. After finally winging with Hayato, she gains access to her Norito, a prayer that unleashes her full potential in an technique known as Ice Erosion, demonstrating a power level that is both devastating and, for a time, fatal to herself.