Anastasia:

Anastasia was born sometime between 1832 to 1866,and lived to be about twelve years old as mostly human. Her mother was an banshee, and her father a demon hunter. She she passed on, a personal situation caused her to transform to fully demon, and she awoke between 1886 and 1888, matured by her experiences and years, however with entire amnesia. She was rescued on the streets by the Earl of Phantomhive, Ciel, and his Butler Sebastian Michaelis. (In the majority of her cannons, anyways.) She lived out the rest of her days residing within this manor, nursed back to health by Sebastian. This information varies slightly depending on which life you are referring to, however it is a common theme for her to have resided within the Phantomhive Manor. She is a feline demoness and banshee, a major hint to this being her long and wavy white hair, feline yellow eyes, and a white fluffy tail as well as two cat ears. Personality wise, she is a rather reserved and nervous individual, soft-spoken until you've gotten to know her well.

Sona Michaelis:

Sona was born sometime extremely early in human history. In fact, her time of birth is entirely unknown, and it is likely that she was born in a separate realm from which she then resided later in life. She grew up in a small village with a young boy named Malphas, whom she was very close with. In time, the two became demon due to an event, then following this began to live in a realm not yet touched by humans. When matured, Malphas and her became mates. She lived with him for centuries, before falling to the tragedy of death by angels. Her child remained unborn, and unknown to Malphas. She was later reincarnated as Anastasia. In life(?), Sona was courteous, thoughtful, and intuitive. She now is a protector to Anastasia, and has become more dark, quiet, and analytical.

Crystal Elric:

Crystal "Okami" was born and/or created between 1900 and 1904, with know real name, and no true home. She was a feline Chimera created by sickly curious scientists, and lived to be approximately 9-12 years old before escaping, to live a real life. She went under the last name "Okami" for the majority of her life, primarily because she thought it sounded cool, but also because she despised being a cat, and felt that people would mistake her feline ears and tail for that of a wolf if she named herself after one. She met the Elric brothers at the age of 12, and studied under Ed's tutoring to become a state alchemist at the age of 13. She was then paired with Ed through the military, mainly as an excuse for the military officers to not have to let two thirteen years old travel nearly alone. She became incredibly close with both brothers, helping them on their search for the philosophers stone, and married Edward Elric after their journey came to an end. Externally, Crystal is a pessimistic stick in the mud who will be stubborn and non compliant as possible until things get serious. She's very quiet until she feels she has to speak her mind, however if you get close to her, rumor has it she's actually a kind, sweet, and compassionate girl. She wears dark clothing, and had long, messy dark brown hair that had blue highlights. Her eyes ranged from ice blue to golden, shifting on her mood, and her cheeks and nose seemed to always have a sickly pink tint.

Katara:

Not much is known about Katara at this point in time. She was born to a tribe of banshees in the forest, her being the elfish princess. She's a reincarnation of Sona, however in what time period I am uncertain. She at one time was a bubbly and sweet girl, but after becoming lost for some time, married a rather dark and mysterious non human man. She then became the Queen of a dark realm, being increasingly formal. She still has a soft side, incredibly hidden. Like Anastasia, she had extremely long white hair. What differs was that her eyes were a sharp red.

"The Apprentice":

The girl was born long, long ago, however she cannot recall much from her youth. She was chased through the deep, mossy and foggy forest by a small group, attacked and left unconscious to be picked apart. She was saved by a woman with long, reddish orange hair, whom she learned to become one with nature from. She studied under this woman who lived in the woods, and recalls seeing a mysterious hooded old woman with silvery hair hunched over their old oven from time to time. She also recalls gardening quite a lot, and foraging in the woods. She was always cautious of those she was unfamiliar with, and feared for the woman she lived with every time the woman went into town. The girl cannot recall her own appearance, however she feels connected to both blue and brown eyes, and feels she had either blonde, brown, or orange hair.