|Age||Unknown, At least 5 years as an arbiter|
|Anime debut||Episode 1|
|Seiyū||Tomoaki Maeno (Japanese)|
Alex Organ (English)
Decim (デキム Dekimu) is the bartender of Quindecim and an acting arbiter for the dead. His faction deals with people who have died at the same time.
Decim is a tall, lean man, with pale-colored skin and bright blue eyes. His white hair is messy, with most of his long, uneven bangs covering the right side of his face.
He wears a bartender uniform consisting of a white long-sleeved button shirt, overlaid with a black vest and a red bow tie. On the bottom, he has black pants, with a black apron over the top, and a pair of black leather shoes. He puts a pin on the left side of his vest.
Decim appears to be emotionless and serious during his job, unless something out of the ordinary or shocking happens. He is very detached in his manner of speech, and would rather not bring personal feelings to the table. He takes pride in his role as an arbiter, and is always respectful towards guests, especially to those who lived their lives to the fullest. Even though Decim has been an arbiter for five years, he still lacks understanding of human emotions, and still shows incompetence at some parts of his job. He has a hard time understanding Machiko’s feelings during her trial, and after Onna explains to him her opinion, he becomes shocked and feels ashamed of his decision, as well as being an arbiter. There was also a time when he was supposed to cancel the game because he didn’t receive the memory of one of his customers, but he still continued anyway, much to Nona’s irritation. However, throughout his years as an arbiter, he still developed an ability to care for his customers in ways such as cracking jokes in unusual moments which doesn't really work, or hugging them when they're desperate, congratulating them for their hard work in their lives. He tries his best to do the right things from his point of view, and doesn't hesitate to learn from his assistant's point of view either.
He takes his job as an arbiter seriously, believes everyone can and should be judged, and that, as an arbiter, he would judge them. This was also shown when he felt ashamed of his decision of sending Machiko to the void, saying he failed as an arbiter in that case.
He also doesn’t like violence, as he covers his eye when Nona attacks Ginti, or how he states that he never usually engages himself in a brawl against the more volatile Ginti, who seems to have attempted to fight him before. However, this also shows that he can become angry if someone insults those close to him, and that he is protective of those he truly cares for.
When a couple named Takashi and Machiko arrive at Quindecim bar, Decim tells the couple to play a game and if the couple refuses something bad will happen. The couple gets darts, with each slot showing a part of the body that will affect the other person. Decim tells the couple that if they don't wish to be harmed, they can miss until someone loses all their darts. During the match Takashi asks Decim if he could use another player's darts, and to which Decim replied that it only matters where the dart is going. When Takashi tries to stab Machiko, after pulling the darts from the board and running towards her, Decim intervenes and stops Takashi by restraining him with his threads. Afterwards, he sends Takashi to reincarnation and Machiko to the void.
Threads: Decim can create threads and use them to restrict rude customers from moving, or use them to hang things. They are strong enough to stop a person in their tracks and swing them hard against the wall. Some of the more offensive aspects of these strings were seen in Decim's battle against Ginti, where they were strong enough to stop the water balls Ginti threw at him, despite their speed and strength, and could grab Ginti's wrist and swing with enough force to throw him across the room and smash through the water tank. He was even able to use them to carry many chairs at once and throw them swiftly and strongly against Ginti.
With Chiyuki around, he begins to understand humans as they share what they think of their customers. He takes into account her opinions and reactions to the games, watching her closely as he makes his judgment. With this, he finds her "fascinating" because of how fresh her personality and opinions are. He is also shown to care enough for her, to the point that he becomes angry as he engages in a fight against Ginti, after the latter knocks her out and insults her because she is human. However, after the judgement between Tatsumi and Shimada, their relationship becomes somewhat strained, as Chiyuki becomes angry at Decim for forcing the darkness of their hearts to the surface and judging them to both go to the void, stating that humans are not as complex as he thinks they are, that they can get angry or sad over little things, and that he shouldn't judge them based on the darkness of their souls. She states he is as bad as Tatsumi, the serial killer-detective who watched innocent people be assaulted, to judge their assaulter and kill them. He only watched their pain, and drew out their darkness to its maximum. It appears at this point that Decim is finally beginning to feel humans emotions, as he grabs his chest, shows signs of pain in his heart, and merely stares at Chiyuki in shock, as she punches him in anger over what he has done. In episode 10, the two are still somewhat awkward around each other, but Decim manages to prompt her to play old maid with their next guest (who comes alone), and Chiyuki begins to remember who she was. It is at this point that Decim wishes to spend the remaining time they have together getting to properly know and understand each other, while learning about human emotions. By episode 11, the two have patched things up, as Chiyuki finally remembers who she is and she begins to discuss with Decim about her life.
Decim's superior. She often scolds Decim when he makes wrong judgments, and sometimes thinks that he is hopeless. However, every time Nona disciplines him, he always keeps in mind what she says and does his best to meet her standards. Despite Nona being disappointed with him sometimes, she still prefers him over the hot-headed Ginti.
He and Clavis don't interact much, but they seem to get along, as they greet each other politely, and Clavis tells Ginti to leave Decim alone as he had his own way of doing things and to respect that.
- (To Misaki) - "Life is always full of unfairness."
- "I have respect for those who have lived a full life".
- "Memento mori. Apparently, it means: Remember that you must die. Do not forget that you will surely die someday, and as such, that is the more reason to live now--is the message contained in that phrase."
- (To Chiyuki) "Judgement must be performed hand in hand with both life and death, it is something that must be performed hand in hand with human emotions."
- Decim's name seems to be derived from his bar, much like the other named Arbiters.
- He collects the dummies of those who have visited his bar and have lived a fulfilled life, as proof they existed, despite of, or because of, the fact that arbiters periodically forget the people they judge.
- His name may also be a reference to the name of one of the Fates from Roman mythology, Decima. Decima measured the thread of life, which may also refer to the threads that Decim occasionally uses to restrain people.
- Decim is an abbreviated form of the word quindecim, the name of Decim's bar, which in Latin means fifteen (the floor that he works on.)
- Nona says he makes the best cocktails, and Quin has complimented him on this skill.
- He has only been an arbiter for five years.
- His bar is a more modern, English style bar, as compared to Ginti's classic, Japanese bar.
- Decim's games usually involve pain and/or body parts.