Haruya Shiki

Haruya Shiki (四木 春也 Shiki Haruya) is a prominent member of underground organization Awakusu-kai. He frequently asks Celty and Shinra to do jobs as a favor to him, so much so that he is the only person outside of Shinra's immediate family that has a spare key to their apartment.

He also appeared in Episode 12.5, where he was seen dealing with a group who attempted to deal against the Awakusu-kai by luring the men to a warehouse and splashing them in glow in the dark paint to beat them in the dark with ease.

Characteristics
Although it doesn't initially seem like it, Shiki adheres to a strict code of honor especially when dealing with clients. He addresses guests with the utmost respect no matter who they are or what their background is, however, he keeps an intimidating aura around him at all times so as not to seem weak. He is also very perceptive as shown when he is able to read Celty's mood through her body language as well as being one of the first people to seriously consider Shizuo not being responsible for the murders that took place in volumes 5 and 6 even without Shinra's help.

Saika Arc
Shuji Niekawa questions him about the strongest man in Ikebukuro. Shiki replied with Shizuo Heiwajima, and then teases Shuji and talks about his daughter, causing Shuji to not use the tape.

Hollywood Arc
Shiki is discussing the nature of the request given to them to capture the serial killer "Hollywood" by Yadogiri Jinnai. The mission got several members of the Awakusu killed and Shiki blames Yadogiri for intentionally giving them false information. Shiki puts out a reward for Yadogiri and finds out the Hollywood is actually Ruri Hijiribe. Shiki goes over to Shinra's apartment and finds the young doctor wrapped in a cocoon made of Celty's shadow. He asks him about the true nature of Ruri Hijiribe and Shinra promises to tell them if they untie him.

Dollars and Blue Squares Arc
Shiki calls Celty over for another job. Shiki tells Celty to make herself comfortable and says it's okay for her to remove her helmet. When Celty does so, one of Shiki's subordinates cries out in fear. Shiki bashes the man's face against the corner of a desk and makes him apologize for being rude to an honored guest. Shiki soon gets to the point of the invite and asks Celty to do two things. The first is to keep her eyes and ears open for clues to the whereabouts of Yadogiri Jinnai although she doesn't have to do any real investigating. The second, and primary job is to locate and protect Akane Awakusu as she hasn't been home for several weeks and she might be in danger.

After Shizuo is put under suspicion for murdering members of the Awakusu, Shiki goes over to investigate. He soon receives a report that Shizuo was found but that he only ran away instead of staying to fight like they expected. They also report that Akane was also seen with Shizuo the day before and that he was also spotted near Shinra's apartment. Shiki along with several of his subordinates go over to Shinra's and question him about what Shizuo was doing over there. Shinra tries to call Shizuo but doesn't get an answer. Shinra starts complaining and mentions Akane which causes Shiki's subordinates to surround Shinra. After explaining the situation to him, Shiki shows Shinra the photos of the deceased. While Shinra does admit that it was done with bare hands, if it was Shizuo, there'd be a bigger mess to clean up and no bodies to identify. As the conversation continues, Shinra starts to ramble on about his love for Celty which nearly puts Shiki to sleep.

Shiki begins to wonder who would benefit from killing three of their men with the Awakusu's rival, the Meidei group, being near the top. His thoughts are interrupted by the arrival of Akane and Celty. Shiki welcomes Akane warmly but the little girl is afraid, mostly due to the fact that Shiki will have to tell her parents. Shiki tells Akane that they will only be happy that she is safe but warns that she might have her cheek slapped. Shiki calls Akane's father, Mikiya Awakusu, and they meet him outside the apartment building.

As Mikiya hugs Akane, Shiki sees a flash bomb thrown by Sloan and shields his eyes. The flash bomb goes off and disorients many of the Awakusu members surrounding them which gave Sloan the opportunity to recapture Akane. As he assesses Sloans' imposing figure, he suspects that it was Sloan who actually killed those men instead of Shizuo. After Akane is returned home and the fighting dies down, Shiki meets with one of his colleagues, Kazamoto, and discusses the murders. It is revealed that the three who were killed were actually spies from different organizations. One from the police, one from Asuki group, and one from a foreign corporation. Shiki hears Mikiya fuming about Sloan's betrayal in the other room.

Adabashi Arc
Shiki sends Sloan to the meeting at Izaya's place as a way to keep tabs on the information broker.

Dragon Zombie Arc
Shiki and Izaya are discussing another job he has. He tasks Izaya with digging up information on two groups. The first is a group called "Amphisbaena" that is running an illegal gambling parlor in the Awakusu's territory. The second is to investigate a group called "Heaven's Slave" that is selling an illegal drug, also in the Awakusu's territory. Izaya accepts the Job and Shiki drops him off in front of the Rakuei Gym since Shiki is also supposed to pick up Akane from her martial arts training.

He does this to test if she recognized Izaya as one of her captors but she doesn't know his face so Shiki drives away, telling Izaya not to fail. Shiki contemplates simply killing Izaya off but reconsiders due to the possibility that Izaya may have ties to other organizations that could backfire on them later. He also wonders why Shizuo went to the room where the three spies were killed (Izaya had known about it and used that to frame Shizuo, but Shiki never found out) and also if Izaya was connected to Akane running away from home. He decides to focus on Amphisbaena and Heaven's Slave and worry about everything else later.

After Izaya turns Amphisbaena and Heaven's Slave over to his side, Shiki meets with him again. Izaya gives him very little info regarding the two groups (only accepting a fraction of the original payment as a consequence) and proceeds to leave. Before he goes, Shiki tells Izaya not to get overconfident, especially with the Awakusu.

Serial Kidnapping Arc
Shiki is called in by Mikiya to discuss the kidnappings that have been going on lately, due to the fact that the police suspect them. The two discuss the rumor that the headless rider is behind the kidnappings. Shiki tells Mikiya that it really has no head, as Dougen is already aware, and that he would introduce the two one day. Due to his growing concern for his daughter due to her interest in the headless rider, Mikiya asks Shiki to speak with it. Shiki then informs Mikiya that the Headless Rider has been on vacation for at least half a year.

Trivia

 * As stated by Kazamoto, Shiki is one of several members of the Awakusu-kai to be a fan of Ruri Hijiribe.
 * Shiki's first name has not yet been used in the novels, and was first released on the official Durarara!! website.