Rikiga is portrayed as a boisterous and somewhat flamboyant man, maintaining a surprisingly upbeat and energetic attitude despite living in the harsh conditions of the West Block. While he initially comes across as morally questionable working as a pimp and engaging in various illicit activities he is also shown to be resourceful and street-smart, with a wide network of contacts.

Early in the story, Rikiga causes tension by offering Nezumi a job in prostitution, a suggestion that enrages Shion. Despite his questionable ethics, Rikiga gradually forms a bond with Shion and becomes a dependable ally. His initial self-interest gives way to genuine loyalty, and he later proves himself a useful and trustworthy member of the group fighting against No.6.

Rikiga is a middle-aged man with short brown hair that is noticeably thinning at the top, giving him a slightly balding appearance. He sports a small handlebar mustache along with a short beard, contributing to his somewhat scruffy look. His eyes are brown, and he has a stocky build, appearing slightly overweight. His overall appearance reflects both his age and the rugged lifestyle of someone who has long lived outside the structured society of No.6.

Before the construction of the wall that separated No.6 from the surrounding areas, Rikiga worked as a freelance journalist within the city. His work, which often critiqued or exposed aspects of No.6 society, ultimately contributed to his exclusion when the city began sealing off those deemed undesirable. As a result, Rikiga was left behind in the West Block when strict entrance regulations were enacted, forcing him to adapt to the lawless and impoverished conditions outside the city.

Rikiga first met Karan, Shion’s mother, when they were younger. Their meeting was prompted by an article Rikiga had written about No.6, which Karan had read and found compelling. Interested in the subject, she arranged to meet him at his office to discuss the piece. Rikiga developed romantic feelings for her at the time feelings that may still linger in the present, though they remain unspoken.

Rikiga is first introduced when Karan, Shion’s mother, instructs Shion to seek him out after learning of her son’s location beyond the walls of No.6. Although Rikiga offers to look after Shion, he quickly draws the boy’s ire by crudely suggesting that Nezumi take a job as a prostitute. Offended by the remark, Shion and Nezumi leave. Despite the rocky start, Rikiga gradually forms a closer bond with Shion and eventually becomes a valuable ally.

Over time, Rikiga’s involvement deepens, and he plays a key role in assisting Shion and Nezumi in their mission to infiltrate the Correctional Facility within No.6. His connections, street knowledge, and willingness to act despite personal risk contribute significantly to their plan’s success.

Later in the series, Rikiga is seen sitting beside a wagon, accompanied by Inukashi’s dogs while caring for the infant referred to as Shion Jr. Upon seeing Inukashi return, he hands the child over, noting the mother’s return. Despite his gruff attitude, Rikiga’s actions reflect his growing sense of responsibility and concern for those around him.

Rikiga also shows a particular disdain for Nezumi, especially under his stage persona, Eve. Each time Eve is mentioned, Rikiga’s mood shifts noticeably he adjusts his hat, expresses irritation, and refers to Nezumi as an “insolent creature.” He is notably resentful that Nezumi continues to issue instructions, even after the main events have passed.

When one of Nezumi’s messenger rats arrives with a letter, Inukashi asks whether he thinks Nezumi and Shion will ever return. With a touch of melancholy, Rikiga replies that it would take nothing short of a miracle for them to come back.

Shion
Rikiga grows deeply attached to Shion over the course of the series, frequently praising his kind and selfless nature. He refers to Shion as an “angel” and often expresses admiration for his goodness particularly in contrast to the harsher personalities around them. Rikiga goes out of his way to assist Shion, such as offering to buy him a new coat after noticing how worn and dirty his current one had become. His respect for Shion ultimately strengthens his resolve to support the group’s efforts against No.6.

Nezumi
Rikiga shares a strained and antagonistic relationship with Nezumi, whom he frequently describes as rude and arrogant. He once refers to him as an “arrogant prick,” highlighting his frustration with Nezumi’s dismissive and sarcastic attitude. Despite this, Rikiga acknowledges Nezumi’s talent as a performer, often referring to him by his stage name, Eve. He admits that he was once a fan of Eve’s performances, though his admiration diminished after seeing how Nezumi behaves off-stage.

Karan
Rikiga and Karan, Shion’s mother, share a personal history from their younger years. Karan first approached Rikiga to discuss an article he had written on No.6, which she had found compelling. Their meeting led to a brief closeness, and Rikiga expressed romantic interest in her. Though Karan ultimately turned him down, Rikiga’s feelings appear to linger throughout the series, as he remains fond of her and protective of her son

Inukashi
Rikiga initially clashes with Inukashi and shows little patience for their blunt and combative personality. However, their relationship evolves as the story progresses. The two end up risking their lives together during the infiltration of the Correctional Facility and learn to rely on one another. By the end of the series, their interactions suggest a grudging friendship built on mutual respect and shared experiences.