Slightly above average height for his age, Rikei has messy brown hair and dark eyes. Like most other members of the Asia Branch Science Division, he wears dark pants, a white dress shirt with a black vest and a dark necktie under a white lab coat. He keeps the sleeves of his coat rolled up, though, and has a black band on his right wrist.
Rikei is the more laid back of his friends, Shifu and Rohfa, addressing Bak Chang , the head of the branch he works for and his boss, in a very informal tone and frequently teasing Rohfa about her crush on Allen Walker.Despite that he has a similar crush on Lenalee Lee. Rikei showed to have a pragmatist point of view in opposition to his friend Roufah's idealism. He believes that the third exorcists are necessary sacrifices to win the war.
Edo and Asia Branch Arc
Rikei is first introduced alongside Rohfa and Shifu at the beginning of Allen Walker's training, the trio wanting to see the use of Innocence firsthand. When Allen initially seems to be able to invoke the particles of his Innocence, Rikei watches in awe as Allen's arm forms. When the invocation fails, though, and repeatedly, he brainstorms with Bak, Rohfa and Shifu, suggesting that Allen's Innocence is simply too far gone to be invoked.
Even after being banned from watching Allen's combat training with For, Rikei sneaks back with Rohfa and Shifu, teasing Rohfa about her crush on Allen. When it seems like For has cut Allen's head off, Rikei is stunned, quickly recovering when Allen passes out after For informs him that she's too tired to cut his head off. When Bak notices them in the room from the observation golems, he puts Rikei and his friends on archive cleaning duty indefinitely, leaving Rikei to carrying Allen to bed.
Later, when Allen gets frustrated with being forced to remain at Asia Branch and takes his anger out on For, Rikei is seen restraining Allen while Shifu restrains For to keep the two from attacking one another. Shortly after, the Akuma Thread infiltrates Asia Branch by breaking directly through For's barrier, shocking Rikei, who wonders how a seal that has protected Asia Branch without fail for one hundred years could be broken.
Rikei rushes to Allen's side and catches him when he is attacked by Thread, carrying Allen to safety when Bak uses the power of the seals within Asia Brach to distract the Akuma. When Bak warns Rikei to be careful with Allen, as Thread's attack has left Allen's particles on the verge of breaking and the slightest jostle could break him apart, Rikei panics.
For then copies Allen's visage in order to distract the Akuma, and Rikei attempts to restrain Allen when he tries to go after her. During the struggle, when Rikei has Allen restrained, Allen threatens to tell Komui that Bak has been taking pictures of Lenalee, something Rikei overhears. Allen then rejoins with his Innocence, leaving Rikei, who was caught in the crossfire, stunned but unharmed.
After Allen defeats Thread, Rikei, along with Rohfa and Shifu, are assigned to studying the newly acquired Noah's Ark and collect data for the European Branch to study, and the trio daydream about joining headquarters, though Rikei and Shifu stare at Rohfa when she daydreams about being close to Allen, instead..
When Allen prepares to leave through the Ark, Rikei, Shifu and Rohfa come to see him off, giving him his playing cards back and explaining that they inked a new ace of spades for him as his deck was missing the card. As Allen departs through the Ark, Rikei is seen comforting a crying Rohfa.
Third Exorcists Arc
Much later, after the creation of the Third Exorcists, Rikei is seen helping to restrain an upset Bak to keep him from storming into Central. When Yu Kanda arrives just then to speak to Zu Mei Chan, Rikei is forced to help Zu find his hearing aid, later berating the elderly man for hiding it in his underwear. Rikei and Rohfa then notice the arrival of Lenalee Lee and Allen Walker, their respective objects of affection.
Rohfa notices that the Third Exorcists have arrived with Allen and Lenalee, and as she, Rikei and Shifu lead the group to meet with Kanda, who they have come to fetch, Rohfa reflects on how she understands Bak's anger at the creation of the Third Exorcists. Rikei, however, defends the idea of their creation, stating that until new Accommodators are found that the military forces need to increase. This upsets Rohfa, making her cry, which makes Allen and Shifu force Rikei to apologize to Rohfa.
- Rikei likes gaming, his friends and Lenalee and he dislikes milk and cleaning.
- He is one of the few people who knows about Bak Chang's obsession with taking pictures of Lenalee Lee.