Belle is Lithium's depressed twin she can't yet control her powers but she gets excited when her twin gets home so they can talk and bond.
Belle used to be in the chaotics with Lithium, but once her beloved sister ran away with Argon Raimies, a boy their age who adored her, she was devastated. Almost immediately after they left she became severely depressed. Later she left home and found herself a place where she wouldn't harm anyone with her nondeveloped powers.
Belle looks just like Lithium, her identical twin, except that she has curly hair and wears all yellow. she has no weapons but she has mind control powers she can't yet control.
Belle has mind control powers she doesn't use because she can't quite control them herself yet.
Belle lives in a forest outside of her parents house.