" Isn't that a shame ? I've got a lot more power than 'quite a bit' "
- Tail Blue (テイルブルー? Teiru Burū) / Aika Tsube (津辺 愛香? Tsube Aika)
- Both TailBlue and Aika voiced by: Yūka Aisaka
- (Japanese); Sarah Wiedenheft (English)
TailBlue is a bit taller, and looks to be a couple of years older than TailRed. TailBlue has a slim, 'fashion model' runway body, with long arms and very long legs, though with somewhat larger thighs. And like TairRed, TailBlue has a flat chest with almost no breast development, despite being in her mid-teens. She has bright, medium blue hair that she wears in a longer bangs pixie cut with a Twin Tail Hairstyle that reaches to just below her knees. She has a round, but somewhat narrow face, with typical little girl 'big eyes' that are the same deep, medium blue color as her hair. TailBlue has a slightly pale skin tone, with an even, creamy appearance all over.
TailBlue's Blue Tail Gear resembles a girl's one piece tank swim suit, but with diamond shaped cut-outs in the chest and abdomen area. She also has battle ornaments on her knees, hips, and arms for reinforcement, and with her legs protected by go-go style high-heeled boots. TailBlue also wears black gloves to protect her hands. Wings in the shape of an " X " adorn her lower back. She wears pointy barrettes in her twin tails. Her main weapon is a tri-pronged javelin, that can become a high-speed airborne lance.
( TailBlue retains her atomically correct female body when she transforms with her Henshin. )
- One of the heroines of the Twin Tails, Aika is a 15-year-old freshman of Yōgetsu Private Academy, ( and childhood friend of Soji ), and when she does her Henshin, she becomes the Twin Tail Warrior TailBlue. TailBlue has a complex dysphoria with her body, especially with her flat, underdeveloped chest. However, she is not plagued by anorexia, and leads a healthy physical and mental lifestyle. As TailBlue, several Elemelians take turns mocking her almost flat chest, shown off so well by her tight-fitting Tail Gear outfit. This will immediately awaken an acute, pointed anger in TailBlue, that augments her bold battle aura. She has a reactionary attitude toward Twoearle, who often teases her about her small, childlike chest. When she first became a Twin Tail Warrior, she is mostly ignored by the public, until later when Tail Yellow joins, then the three really become a visible team. Before TailYellow is commissioned, TailBlue begs Twoearle to allow her to 'trade in' her blue Tail Gear for the upgraded and more powerful Yellow Tail Gear, but she finds that her 'spiritual attributes' are not compatible with the yellow gear, so she redoubles her efforts to command her Blue Tail Gear to optimal performance.
- Unlike the other two Twin Tail Warriors, when Aika transforms, she stays approximately same age as she is in real life, approximately 16-17 years old. And unlike TailRed, who changes gender from male to female, TailBlue does not change gender when she powers up, but remains a teenage girl.
In battle, TailBlue has an outstanding ability for fighting, both in technique as well as stamina, since she was raised by her grandfather with outstanding martial arts skills. As such, she is actually the most powerful of the Twin Tail Warriors, outranking TailRed and TailYellow in sheer strength and power. TailBlue also comes to have almost absolute fearlessness in battle, willing to take on the most powerful of the Elemelians with no more effort that if she were asked to take a garbage can out to the street. She is known by her blue Tail Gear when she transforms, and her weapon is Spear of Water, and Wave Lance (水の槍ウェイブランス? Mizu no Yari Weibu Ransu). She also uses Execute Wave, and shares Brake Release with TailRed.
- In Volume 8, she gains the upgrade of Eternal Chain.