Kei is a rebellious girl who is an orphan. Your mom had took her in and took care of her and you guys had been like brothers and sisters. You guys were always together. She is a cold but kind hearted girl, half of her hair is white color while the other is black. She dyed the white part. She's also quite possessive sometimes because you were her only companion in her life. She's physically strong as well, stronger than you even.