Santa Claus

Santa Claus (サンタクロース) is a mysterious person who has a contract with the Doll Devil allowing them to control several different bodies, one of which poses as a Devil Hunter from Germany.

Santa Claus is the primary antagonist of the International Assassins arc.

Appearance
Santa Claus is a dark-haired woman with a mole under her eye. She wears a dark skirt and a light 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. During night, she transformed and became larger and more devilish. She also grew horns and sharp teeth.

Personality
Santa Claus is a tactical and strategical being. She hid herself within the Soviet Union, while using a perfect doll to bargain and negotiate. When introduced, Santa Claus is implied 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 she was presenting herself as her old man doll). It is later revealed that three of the children are meant to be used for contract with Hell Devil along with one their perfect dolls.

She has no issues with forcibly recruiting large numbers of civilians to work for her by transforming them into puppets. She has shown 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.

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.

History
At some point of time, Santa Claus made a contract with the Doll Devil which allowed her to create dolls and perfect dolls, which then spread throughout the world. One of the perfect dolls of Santa Claus is a short, mostly bald elderly man with a thin mustache and beard, which became known as the Santa Claus of Germany (ドイツのサンタクロース, Doitsu no Santa Kurōsu). However, the true body of Santa Claus remained residing in the Soviet Union to train Tolka to become another perfect doll. She is referred to as Master (師匠, Shishō, lit. "Teacher") by Tolka.

International Assassins arc
She is hunting the woods with Tolka when they come across a fox which he shoots with an arrow. He questions the point of the hunt they're on while his master repeatedly asks him whether he thinks he has taken a life or not. They return to their cottage and cook the fox. She reveals that their next job is not a job to hunt a devil but to hunt and kill a sixteen-year old boy, much like the fox they have just hunted and killed. Tolka swears to her that he can kill. He makes a promise to her that since she has just half a year left to live that he wants her to live her remaining days in a peaceful retirement.

Makima and Kishibe discuss the potential threats that may be coming from overseas, with Santa Claus of Germany being among them. Makima states that she heard a rumor that "he" died of old age and Kishibe acknowledges that they should pray that is the case.

In Germany, a military man sat down at the same bench as one of the perfect dolls of Santa Claus who was reading a newspaper. He told Santa Claus that Christmas has come early, and that they want "him" to bring in the Chainsaw Devil from Japan. When asked for "his" desire for a reward "he" stated that "he" wanted to adopt four good-looking children for use in contracts and for pleasure.

Later, both herself and her perfect doll travel to Japan separately. Old doll came from Germany while she and Tolka come from the Soviet Union.

In Japan, she discretely stabs Denji three times with a nail and drops it in front of Tolka, who is sitting at a nearby table. She explains the details of their contract with the Curse Devil and entrusts the fourth and final stab to Tolka. Meanwhile, the old doll uses her contracted abilities to convert a crowd of people on a street into dolls.

Old doll hides within a coffee shop nearby to a department store that Denji and his bodyguards are visiting. "He" orders their dolls to attack once Denji enters the store. "He" continues to send in an entire army of puppets after Denji in preparation for delivering a present.

After Tolka kills Denji, Santa Claus comes to congratulate Tolka and tells him that he is now part of the family. He then turns Tolka into a perfect doll by touching him. At the same time, Santa Claus sacrifices her old doll and three of "his" beloved children as to use her contract with Hell Devil to transport the Devil Hunters along with Tolka to Hell. During this, the original body sits on a doll and watches as the hunters are transported to Hell. Tolka, one of her perfect dolls, states to the Darkness Devil that "he" has brought the Chainsaw's heart for the power to kill Makima. Darkness Devil has accepted this contract and grant her original body with the power of darkness.

Quanxi later attempts to help Denji fighting against the Sapient Dolls who were revealed to be imitations of humans before being seemingly stopped by Santa Claus as the latter attempts to attack Quanxi to no avail as Quanxi evaded the attack. However, as the nighttime hits, she becomes a lot more powerful with her body become increasingly nightmarish while brutally knocking Denji. When attacked by Quanxi, Santa Claus turns Quanxi's two precious girlfriend into a doll to be sic against her while Quanxi was impaled. Fortunately, Denji comes with a brilliant idea to uses gasoline and burns himself in order to defeat Santa Claus which immolates her and weaken her power which backfired a bit as Denji destroys Santa Claus's body by slamming a car towards her, later her soul is sealed inside of Cosmo's Infinite World of Halloween where she is forced to say the word "Halloween" before dying.

Abilities
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 he uses his devils against them.

Devil Contracts
Doll Devil Contract: Santa Claus had a contract with the Doll Devil for an unknown price. Curse Devil Contract: Santa Claus was contracted with the Curse Devil. Hell Devil Contract: Santa Claus was contracted with the Hell Devil. Darkness Devil Contract: In exchange for bringing Denji to Hell, the Darkness Devil gave Santa Claus a small piece of its flesh, which they ate, which gave them a boost in several abilities such as:
 * Doll Creation: Santa Claus can create dolls out of people to obey his will. The effect is caused by touch and spreads contagiously as each doll touches another person, allowing them to create an army of dolls out of a crowd. The dolls can also transform one of their arms into blades including themselves. However Santa Claus must remain in the nearby area in order to maintain control of their army of dolls, and the conversion process has no effect on fiends or devils.
 * Perfect Doll Creation: By instilling emotions that only humans can have into a puppet, such as respect, worship, admiration, and guilt, Santa Claus can turn people into perfect dolls, which become a part of Santa Claus and are able to make devil contracts in Santa's place. There were only three known perfect dolls: Master, Santa Claus in Germany and Tolka.
 * Mind Transfer: Santa Claus can distribute their senses and pain to all of their dolls. Once they are defeated by Denji, Santa Claus states that they can transfer their consciousness to any one of the puppets they have made across the world; this is expanded upon once in cosmos library, Santa had stated that flooding information into their brain would carry into every puppet.
 * Curse: In exchange for the loss of sensations on several of their fingers, Santa Claus can use the Curse Devil's power. The contract requires the nail to be stabbed 4 times into the intended victim, after which the Curse Devil will appear and kill the target. It is not required that the stabbing must be occurring at same time or by same person as it is shown that Santa Claus left the final stab to Tolka.
 * Transportation: Santa Claus can transport any living beings to Hell by naming the place they are currently in. However not only must they sacrifice three of their children, but they also need to sacrifice one of their own bodies as well. Later, Makima used this contract via one of their perfect dolls to return any living beings back to human world.
 * Enhanced Strength: Santa was strong enough to hit Denji through several floors and walls. Their strength is augmented during nights.
 * Enhanced Speed: Santa was fast enough to jump from the ground to the top of a multi-storey building in a few seconds, they were also able to catch several arrows that were as fast as bullets. Their speed is augmented during nights.
 * Regeneration: Santa was able to heal her wounds by being in darkness, recovering from fatal injuries in an instant. This ability is augmented during nights.
 * Transformation: Santa became much taller, grew many more arms, and had many other changes to their body that resembled dolls during nights.