Decim

"With Decim, it’s all drinks and seriousness. Aside from that, he has no other saving graces.""

- Nona, giving a portrayal of Decim in Episode 2 "Death Reverse"

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.

Appearance
Decim is a tall 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 atop and a pair of black leather shoes. He puts a pin on the left side of his vest.

Personality
Decim appears to be emotionless and serious during his jobs, 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 years, he is still lacking on understanding human emotions and still shows incompetence at some parts of his job. He has a hard time understanding Machiko’s feelings during their 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 only doubted it and still continues anyway, much to Nona’s irritation. However, he is developing these areas and has lightened up a bit from his stoic nature thanks to Onna’s influence. He cracks jokes to his customers (which he didn't usually do before) or gives them leeway before departing. He even shows some compassion as he hugs the customers who broke down and cried about losing their lives, saying they have lived to their fullest and should not be ashamed.

He takes his job as an arbiter seriously and 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.

Death Parade
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 will have to miss until someone loses all their darts. Throughout the match Takashi asks Decim if he could use another player's darts and to which he replied that it only matters where the dart is going. When Takashi tried to stab Machiko after pulling the darts from the board and starts running towards her, Decim then intervenes and stops Takashi by restraining him with his threads. Afterwards, he sends Takashi to reincarnation and Machiko to the void.

Abilities
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 one of the water tanks. He was even able to use them to carry many chairs at once and throw them swiftly and strongly against Ginti.

Chiyuki
Chiyuki is a customer who came to Decim's bar after she died. However, because she still had most of her memories intact and knew the fact that she was dead, Decim had to erase her memories and prolong her judgment time as he couldn't convince her play a game of life and death to judge her. After that, he takes her as his assistant and they started to get along with each other.

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 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 mad as he engages in a fight against Ginti after the latter knocks her out and insults her because she is a "human being". 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 humans are not as complex as he thinks and that they can get angry or sad over little things and he shouldn't judge them based on the darkness of their souls. She states he is bad as Tatsumi, the serial killer detective who watched people be victimized to judge their assaulter and kill them. He only watched their pain and drew out their darkness to its maximum and he was evil. It appears at this point that Decim is finally beginning to feel the emotions that Nona had placed in him as he grabs his chest and shows signs of pain and sadness over his heart and looks at Chiyuki 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 maids with their next guest (who comes alone) and she 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 and how she viewed herself as worthless after she lost the ability to skate not just because it was her passion, but also because it was what defined her and without it she felt like she was nothing and that those around her couldn't understand her or had a connection with her after she lost the ability to skate, prompting her to depression and later suicide. He tells her humans can't understand each other but that will not stop them from trying to because humans have different ways of expressing themselves and have emotions that allow them the desire to get to know other people and bond with them.

Nona
Decim's superior. She often scolds Decim when he makes wrong judgments and 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. In episode 4, Nona walks in on Decim in bed with a mannequin, and becomes very disturbed with him. This incident had a major strain on their relationship, and it is hinted that this is why Nona is so aggressive with him.

Clavis
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.

Ginti
The two of them do not get along so well, most probably because of the one-sided rivalry Ginti creates between them. Despite that, Decim doesn't seem to hate him as evident when he addresses him formally or when he ignores Ginti’s taunts of fighting to prevent causing trouble. However, when Ginti crosses the line (such as when he attacked Chiyuki), Decim gets angry at his actions and even wins the fight against him.

Quotes

 * (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.."

Trivia

 * Decim's name seems to be derived from his bar, much like the other named Arbiters.
 * He collects the doll-representations of those who have visited his bar and have lived a fulfilled life, as proof they existed.
 * 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.
 * Nona says he makes the best cocktails.
 * 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 grotesque body parts.