Official Art art by shiro
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Hair Reference
Costume sheet 1
Costume sheet 2
Costume sheet 3 

Aoko Seiji
Proper Name: Seiji Aoko
Name Means: Seiji- means "justice" but the kanji used to write her name means "twins". Twins has a special meaning to the Clan/ Aoko - "Blue Child"
Aliases: Takahashi Ao - name use outside House of Seiji, used because the Seiji family has a lot of enemies
Takeda Masahiro, Suzuki Rumiko - other names
Age: 2 years younger than Shuiichi Minamino (she first appeared during the time Kurama went back to Ningenkai to gather demons for Youmi's army…he stayed in ningekai for 6 months ) 
Race: Nai, part Human 
Gender: Female 
Bday: 
Zodiac: 
Bplace: Kyoto 
Family: 
Mother: Linda Carrens (real) 
Father: Julian Carrens (real) 
Siblings: "Mike" Carrens, Linh Meiling (twins sister of Ao), Marhianne Carrens and Raven Carrens 
Others: Grandfather (the one who adopted her) Masao Seiji 
Height: 5'5" 
Weight: its not nice to ask a woman her weight~ 
Eye Color: piercing purple 
Hair Color: raven black 
Likes: to fight 
Dislikes: annoyances
Educational Attainment:  St. Therese's Academy 
Hobbies: training, 
Blood Type: AB 
Weapon: Kotetsu 

Other Facts: 
Head at age 12 
Has long straight black hair, 5'5", eyes in piercing purple, fair skin 
Sly, clever, persistent, tough, stubborn, stiff, highly responsible but sometimes a crazy lunatic…yet sometimes prefers to be in soltitude 
Is a born leader…and will take matters in her own hands~ 
When she was born, (or atleast when Masao-sama found her) an eagle was said to be guiding her… it is Twin spirit … she named this eagle Reikon. 

*The Seiji Ninja Clan 

Several years ago, when the gateway between Makai(demon world) and Ningenkai (Human world) is still open, the Seiji Ninja family is asked to be the guardians of the imperial family of Japan. They protect their Imperial family from humans and demons alike. In order to do this they studied various way of manipulating ki or their spiritual energy…and some even youkai energy-thus was the sword Kotetsu is created. Kotetsu is a sword forged by and with demons-it is a demon sword for it is believe that the best way to defeat demons is by demons them selves...hence the seiji ninjas utilized the use of youkai(demon) energy in their battle over youkais..however Youkai remains to be the Seiji Ninjas enemies…hence they were known more as Demon Slayers than Imperial Guards. The demon sword is passed from one leader to another…hence becoming the symbol of leadership for the Seiji clan.