The woman who gave Shiki his glasses to prevent him from seeing the lines of death in Tsukihime.
Aoko is a member of the Aozaki family, who are a long family line of magi. As a teenager, she came to discover that she possessed Magic Blue, one of the five "true magics" that allow her to manipulate time. Despite having a limited number of magic circuits, she made use of Magic Blue to maximize her potential as a magus and this made her into the lead candidate of becoming the Aozaki family's clan leader. She was normally at odds with her sister Touko as such that she refused to learn of rune magic since it was her sister's specialty.
Aoko Aozaki was a character originally made for Kinoko Nasu's earliest work, Mahou Tsukai no Yoru. The story would later be adapted into a visual novel game, as its existence has only become known recently to the public. She was made into a minor character for Type-Moon's Tsukihime visual novel game. Aoko has appeared in anime and manga adaptations of Tsukihime, as well as Carnival Phantasm. For Japanese adaptations of her character, Aoko was voiced by Akiko Kimura for the Tsukihime anime and Kotono Mitsuishi for Carnival Phantasm. She was voiced in English by Karen Strassman.
Aoko originally had brown hair and blue eyes when she was younger. But due to her use of Magic Blue, her hair color turned red as a result. Her hair is long in length, reaching all the way down to her legs. In Tsukihime, she is seen to wear a white shirt, blue jeans and a pair of brown shoes.
Aoko has a bright and cheerful personality, known to react strongly to careless actions. She came to have a strong attachment to the value of life, the value of which she passed along to Shiki Tohno. Shiki is known to call her "sensei" (teacher) because Aoko hates being called by her name since it sounds like blue ("ao").
Aoko's role in Tsukihime is a minor, but important, one. She encountered Shiki as a boy when he was struggling with learning to accept use of his Mystic Eyes of Death Perception. Aoko taught Shiki the importance of valuing life and gave him a pair of Magangoroshi glasses which seal the effects of his Mystic Eyes whenever he wears them. Shiki would later meet with her as a teenager toward the end of the series to thank her for what he was taught from her.
Aoko is one of the strongest human magic users on record, as such where she is one of the few humans capable of fighting a direct battle against Servants and even able to fight against powerful vampires such as Arcueid and Nero Chaos. She is powerful in both magic and physical combat as such that she is rather destructive when she fights, earning her titles such as Magic Gunner and Human Missile Launcher.
Magic Blue, also known as the Fifth Magic, is one of the five "true magics" that Aoko is able to wield, which gives her the ability to manipulate time. The ability grants Aoko various uses that she utilizes for both combative and non-combative scenarios.
Because of her use of Magic Blue, Aoko's knowledge and use of magic became greatly amplified rather quickly. She is able to utilize her magic in both ranged and close-quarters combative scenarios in the form of highly destructive attacks used against her foes.
For ranged combat, Aoko utilizes a number of magic missile attacks called Starmine and Starbow that take on the form of exploding fireworks and rotating stars. Starmine type spells possess energy with a fluid motion, while Starbow spells are more fluctuating. They are simple spells to execute depending on the amount of magic utilized and Aoko would normally be limited to how much she could expel at once due to her limited magic circuits. But through combination of utilizing Magic Blue and utilizing a technique called Unlimited Rotation to greatly increase the speed of her incantations during battle, Aoko is capable of quickly firing off a multiple number of magic missile attacks at her foes to overwhelm them in battle.
In close quarters combat, Aoko can augment her physical abilities in combat by channeling prana into her arms and legs. Looking like rocket thrusters from her opponent's eyes, the augmentation allows Aoko to cause a great deal of collateral damage with her blows and she can easily punch or kick her way through magically-formed creations such as barriers. In the event she needs more power than what she would need presently, Aoko can place herself under a form of self-hypnosis to further amplify her attributes in battle.