Santa Claus

Santa Claus is a tactical and strategic being. She hid herself in a remote region, while using a perfect doll to bargain and negotiate. When introduced, Santa Claus appear to be a lecherous being who asked for several children of either gender as their reward for bringing in the Chainsaw Devil from Japan, apparently for use in contracts and for pleasure (although this is likely done to instill strong emotions into them and groomed them to be the next perfect doll). It is later revealed that three of the children are meant to be used for contract with Hell Devil along with the old man perfect doll. She has no issues with forcibly recruiting large numbers of civilians to work for her by transforming them into puppets, as well as no regard for those who seem to care for her. For example, when her ally Tolka had subdued Denji, Santa Claus turned him into a puppet to communicate with the Darkness Devil and complete the contract. After absorbing power from the flesh of the Darkness Devil, she begin displaying a more arrogant and haughty persona over her power and intellect, believing that with its power and her dolls she'll continue evolving and come to understand everything, and becomes either amused as she experiences or understands something new or fearful when she sees something she has trouble understanding. Cosmo states that Santa Claus believes that the power of Darkness will let her understand everything, though she proves her wrong when she gives Santa Claus the total knowledge of the universe to let her truly understand everything and drives her mad. During battle, Santa Claus displayed a more ruthless tactic by transmitting her pain across puppets all over the world. In order to eliminate Quanxi, Santa brought back the personalities of some puppets to dishearten and kill Denji.

Santa Claus’s main body is presumed to be a dark blue-haired, green eyed woman with a mole under her eye. She wears a dark skirt and a orange sweater. After she ate a piece of Darkness Devil's flesh, she gained several doll arms and appendages and her legs were made of doll heads from the pile of dolls she was in. During night, she transformed and became larger and more devilish. She also grew horns just like the Darkness Devil has and sharp teeth. In the colored manga, the darker skin of the body at night is a dark purplish-gray while the lighter doll head torso and legs are the same color as Santa’s human skin as the doll heads mimic her original face when she was human. She has 40 eyes on her monstrous form in total, with 10 arms at day and even more arms at night.

Makima and Kishibe hold “him” in high regard as the most dangerous threat towards Denji amongst the world's assassins and devil hunters as they say it will all be over if Santa Claus uses “his” devils against them.