"Even when I get the results, the price I had to pay doesn’t match."
― When Enshuu Mitsuari and Misaki Dairenji questioned why he ended his research

Avery Martinez is a character introduced in the Nightmare Fiction arc as a former member of the infamous Dairenji family, and a key member of POLTERGEIST as Útgarða-Loki.

Knowledgeable in both science and magic, he plays a key role in the workings of POLTERGEIST and the The Foo Fighters, who uses science and magic hand in hand. Behind the coat and a helmet lies a cold and distant former Dairenji who strikes in Destiny City to carry out his revenge on the person responsible for an incident that ruined his life. 

Avery Martinez
15 - 1 (1)
Age 20s
Gender Male
Birthday May, 5th (Taurus)
Blood Type A
Laterality Ambidextrous
Powers {{{Powers}}}
Weapon Anything is a weapon to him
Personal Details
Status Deceased
Alias Black Death


The Heart Break Kid

Occupation Ex-Reacher

Ex-Special Victims Unit Chief

Former Teacher

Ex-Foo Fighter

Affiliation POLTERGEIST (Leader)

Dairenji Syndicate

Hobby World Peace, Teaching and Training students
Favorite Food Fried Pizza with extra cheese and pepperoni dipped in ranch with a side of fries.
Family Misaki Dairenji - Adoptive Sister
Hair Color Black with a white forelock
Eye Color black eyes
Height 185cm
Bust n/a
Cup n/a
Bust Volume n/a
Waist n/a
Hips {{{Hips}}}

What lies in his soul is Grief and Redemption.


Útgarða-Loki is named for the mythological figure from Norse mythology. A Jötnar, his name literally means "Loki of the Outyards" to distinguish him from Loki. His name is often anglicized as Utgarda-Loki and Utgard-Loki.


During the events in Destiny City, he is seen wearing a black coat that covers of his body with a belt tightened around his waist (with the belt buckle bearing a serpent or a dragon), black shoes and gloves, and most notably a black helmet that obscures his identity.

He is a rather tall man, with a lean yet fit build, almost adrogynous, but has a handsome face and a sexy bedroom voice. When his helmet got destroyed, he is seen to have black eyes, and short black hair, which was somewhat spiky.


He is a Dairenji, as such he has a natural affinity to science and the gravitation towards evil. However, he somehow managed to overcome both of this, becoming a Transcendent Majin, as well as helping the audience of Grand Magic Tournament, and other characters. Yet, he is still a Dairenji regardless, as he displays his deviousness, having manipulated events in Destiny City as so he can face Misaki Dairenji equally, as well allowing for the events of Radio Silence, and the invasion of Hawaii to take place. Therefore, he is considered to be like the other Dairenjis. He is someone who will let nothing get in the way to achieve his goals, even if he is good.

As a Dairenji, he commited experiments related to stopping and starting the heart safely and was considered a genius for it. However, he eventually seemed to develop a conscience through his actions and became a teacher, thus abandoning his role as a researcher and betraying the ideals of a Dairenji. After he killed a murderer/child rapist who was a threat to his students; and had even attack seven of them before he intervened, he realised that the scenario was set up by Misaki Dairenji and, despite he himself being acquitted for the crime, he quit his job. Later on, he begins working to bring Misaka down, to avenge the person she turned into a killer and rapist and he himself killed, convinced that justice was not done until either of them was dead.

He also appears to be aware of Victoria Amicus's existence and has confidence in the fact that people who end up involved with her usually come out of things unharmed no matter how bad the situation gets, which led him to advise the seemingly doomed survivors of Destiny city to seek her out.

It is hinted that he had an intimate relationship with Sherria Strauss, his mentor in magic.


Originally, he was a near-death and near-rape experience researcher who eventually gained the ability to safely stop a person's heart and restart the safely stopped heart. He was also able to control the number of times he could stop a person's heart, which made him legendary amongst the Dairenjis. As a researcher, he killed the most number of people out of all Dairenjis, but as he revived those he "killed", no one was damaged by his actions. He ended his research after realizing that since he could kill and revive people easily, regardless of the reason that the value of human life remains the same, it would always be judged at a very low baseline. Basically, he felt that with his skill over life, it could be compared to that of a child turning a television on and off.

He later became a teacher, which was easy as he had erased his past as a Dairenji. As a teacher, he took part in Student Keeper activity, which was one of the safety measures of Kyoto to prevent students being unable to return to the school life due to them skipping class. During the activity, he managed to reach what lied deep inside a student's heart and effectively make the students come back to school, which earned him some fame. He also warned them of the Dairenjis, "the dangerous darkness in Kyoto". He resigned from his job about 3 years prior to the Nightmare Fiction arc's events due to an incident arranged by a fellow Dairanji (Misaka) that corrupted two young men and a young woman and erased them, from the records to attack (and rape) a group of Avery's students (which included Enshuu Mitsuari). He charged towards the attackers, damaged their consciousness and killed them before anymore tragedies could occur. Despite the court's verdict making him innocent and his teacher licence still active, he decided to take revenge on whoever arranged the incident and disappeared from Kyoto.

By that time, he met Sherria Strauss and helped her to improve the Celestial tools that were essential for their survival, while he began to study magic. He also developed spells for the sake of "carrying out the perfect tie against his one mortal enemy", which were deemed too dangerous to touch by POLTERGEIST magicians. Sherria intentionally drawn Avery into POLTERGEIST and he became one of the organisation's science oriented cores that provided assistance when members had to rely on scientific technology to carry out their plans. At this time, Sherria bonded with Avery, and clearly cared for him as a colleague, and is described as being her partner, telling him to return to her if he has finished his vengeance, unaware of the meaning of his version of revenge.

Preparing for the possibility that his mind and body might get controlled if he fails in defeating Misaki Dairenji, Avery implanted a semiconductor in the back of his neck, within it are things that Avery would do given certain conditions. However, a tiny effect would appear only when he was forced to do something that was "not like him". To ensure that he would take actions that were "like him," a list of rules on the device were inputted: 1. He would exterminates his enemy, Misaka Dairenji; 2. As long as it did not interfere with 1, he would limit the loss of life of both enemy and ally as much as possible; 3. To achieve 2, the damage or destruction of anything other than human life was allowable.


Heart Stopping-

Heart Restarting-

Heart Transplant-

Special Ops Mastery-

Detail Intuition-

Medical Intuition-


As his secret identity, Útgarða-Loki, he was the illusion specialist of POLTERGEIST; his illusions are similar to the mold used by Nayuta Mitsuari. His magic allowed him to transfer the information sent to one of the five senses to a different sense. Simply put, he could make someone feel the pain of burning by showing them a picture of fire. Used correctly, that ability held quite a bit of destructive power, but many materials used together in the right way were needed to give a more accurate and long-lasting illusion.

What's more, with his knowledge of the human body, Avery could apply damaging techniques to his advantage, as what happened with the killer he attacked.

Other abilities

Being a Dairenji and a former researcher, Avery has an ample scientific knowledge, especially he is able to safely stop and restart a human heart.

Also, as other Dairenjis, he is willing to use unorthodox and dangerous fight methods, like when he detonated a convex landmine hidden in his coat in order to kill Juvia Dairenji. He proclaims himself an anti-Dairenji specialist.

Avery's Theme

Naruto Shippuden - "Closer" (Opening) ENGLISH ver AmaLee & PelleK

Naruto Shippuden - "Closer" (Opening) ENGLISH ver AmaLee & PelleK



Avery had an extreme coffee addiction, apparently drinking 73-82 cups per day. 

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