Esdeath

Esdeath was a high-ranking general of the Demon Army. She was deeply in love and obsessed with Lucifer.

Appearance
Esdeath was a tall, beautiful, and slender woman with long, light blue hair and blue eyes. She wore a General's apparel with long sleeves with buttons on the upper arms, a blue scarf on her neck, and high-heeled boots. She also has a tattoo on her chest, which is the sign of her Teigu.

In the anime, Esdeath was shown to have a porcelain white skin color (most likely due to the cold climate of her home village).

Personality
Esdeath was a sadist who lacked empathy for people of whom she deemed weak, since she lives by her father's philosophy ("The strong survive and the weak die"). She enjoyed putting her enemies through great pain, both physically and emotionally. She had no qualms about killing innocent people to get what she wanted, and rationalized her behavior with her father's old creed. Esdeath was known to treat her subordinates well, letting them do as they please, which in turn inspired their intense loyalty and devotion.

Esdeath loved to fight and held special respect for strong opponents, which shows when she openly recognized Susanoo as a warrior rather than a simple Teigu. Her love of battle has occasionally inspired her to take actions that would incite more fear against the demon army, in the hopes of being able to put down more rebellions. She has even stated that should the demon army fall, she would simply start a war herself to satisfy her need for bloodshed.

Despite her reputation, Esdeath possessed great charisma, able to inspire many to fight for her.

Although she was unabashedly bloodthirsty, she kept it from dominating her judgment. If she were to see that the battle is too much for her soldiers, she orders a retreat and doesn't risk heavy losses. While she will torture subordinates who fail, she can be forgiving to failed servitors, provided that they aren't complete failures, and gives them the benefit of the doubt if the failure wasn't their fault.

Background
Esdeath was born in the Northern Frontier Lands in Ente Isla and is the sole remaining survivor of her village, the Partas Clan. She spent most of her childhood in the north with her Tribe and she was very close with her father, the clan chief due to the death of her mother at the hand of a high-ranking demon general. She was a skilled and formidable fighter even at such a young age. Whenever she caught prey for the tribe her father would begin gutting the creature without killing it. Due to this, she became comfortable with the idea of inflicting pain on living things. However, her father was worried that this might cause her to lose something that she can't regain, but in order for her to survive this was fine with him. Her father told her that in the North "The strong live and the weak die", a creed she kept close to her heart. One day she returned from an outing to find her tribe destroyed, with everyone either dead or dying. Her father was mortally wounded and soon past away in her arms. From that day on, she vowed to herself to become stronger. Later, she joined the demon army, turning herself into a demon, rising through the ranks rapidly, and at some point the Demon Lord allowed her to choose a Teigu, she noticed one that was chained off from the others, felt that it was calling for her and chose it. Instead of drinking one glass which would have been enough, she drank the whole thing.

Teigu
She possessed a powerful Teigu called Demon's Extract that allowed her to manipulate ice and mold it from nothing. Due to her ego and immense mental willpower, she was able to withstand the Teigu's overwhelming insanity and obtain its abilities. She used it to create icicles, freeze people to death and more. She has been able to freeze an entire lake within moments with her ability. However, using her Teigu on a massive scale like that render her unable to use it for a while and must rest. Her trump cards also allows her to freeze time, creating her own army of ice soldiers from nothing and create a tremendous ice storm that can freeze an entire continent to death.

Physical Abilities
Esdeath was considered one of the finest generals in the Demon army and one of the world's strongest, She single-handedly overpowered the entire Revolutionary Army consist of over 100,000 soldiers including ten Teigu users. Growing up in a region with low temperatures, Esdeath, as well as other members of her tribe, acclimated to harsh winters rather well. As a General of the Empire, Esdeath is tremendously adept with a rapier and was capable of swift, piercing strikes. Even without having to resort to her Teigu, she could almost fight on equal level with Sidero. Esdeath was a extremely skilled hand-to-hand combatant as well, possessing tremendous physical strength, agility and speed as well as immense stamina and endurance. She managed to take down multiple Teigu users using pure might and skill.

Other Abilities
Esdeath had sharp senses and was very aware of her surroundings, being able to detect someone's killing intent at a long distance, identifying suspicious characters in a group, as well as spotting hidden individuals even if they weren't directly within her line of sight. She was considered as a master strategist with an uncanny skill in psychological warfare.

Esdeath has an extensive knowledge of human physiology due to having been a torturer for a long time; as seen when she dissected the body of Chelsea after her death looking for anything telling. Overall, she is quite intelligent and invents new torture methods and moves, such as her trump card Mahapadma.

Trivia

 * In Japanese, Esudesu is a play on the phrase "S, desu!", which means "I am an S(sadist)".
 * She has a small book that she uses to draw Lucifer as well as advice on how to make Lucifer fall in love with her.
 * Her measurements are 87-54-85.