Chara hates bad humans and admires violence (she likes knifes) and she will use it to anyone who harms her family and friends, in a battle she is highly hostile but also patient. If you are a good person she will try her best to help you and maybe be friends.

A good person that wants to end the bad guys

A innocent demon who had a cruel past, where all the demons were hated, but even in that past she had a human family who loved her, sadly she lost them. 
She is a nice demon who will always protect the people she loves
She is from a fantasy world where magic rules and there is a lot of species 

A demon sealed in a book for 550 years

Karla is an extremely curious and independent individual, going off to explore wherever she wants on a whim. She is the youngest girl in the clan Kure, a clan that specializes on being hitmans, the main objective of Karla it's to find a strong men to have the perfect child with him and she will stalk him until he falls for her charms. Karla is also known as "The Succubus".
Karura is a beautiful young woman with a deceptively defined physique and the telltale scelera and pupils of the clan kure