Kio has a large tattoo of a butterfly on his back (it was recently revealed that Soubi only became interested in Kio due to a tattoo on his back, and a vow he took when he got it) and earrings covering both ears.
Kio’s quirks include his sweet tooth, his love of piercings and tattoos, and his habit of calling people by nicknames and the suffix “-chan.” He frequently makes sexual innuendo. He gives Soubi an ear-piercer for Ritsuka to use on his Fighter. Kio comes up with nicknames for most people (Sou-chan for Soubi, Ricchan for Ritsuka, the Chibis for Sagan Natsuo and Sagan Youji, etc.) and sometimes refers to himself as Kio-chan.
Despite his early presence as a character who exists solely to create a lighter atmosphere in a very dark story, he gradually gains depth and justifies his existence as the series progresses. He becomes a loud voice that champions pacifism and self-worth, contrasting greatly with Soubi’s submissive nature that willingly accepts violent treatment and his strong desire to be controlled by others (namely Aoyagis.)
Kio is shown to be extremely stubborn in his beliefs in chapter 45 when he opts to stay outside in front of Seven Voices Academy instead of going to the safety of the hotsprings. Because of this choice, he is kidnapped.
[note to future jess from past jess - rewrite paragraph about kio being insightful with quotes from vol 2 (fear in soubis eyes) and vol 6 (communication) rewrite paragraph about kio's work ethic]
Agatsuma SoubiIn volume 7, chapter 45, Kio says that he is quite possibly Soubi's only friend.
Despite being quite aware that Soubi lives a life quite different from his own, Kio does not know the details. In chapter 45 of volume 7 Kio laments that he thought he would finally know Soubi's secrets as he is being pulled away from entering the academy.
Kio and Ritsuka meet in volume seven, chapter 44. Kio appears quite angery when they met, however he is impressed with Ritsuka's manners. Kio had expected to meet another person much like Seimei Aoyagi.When Kio sees how upset Ritsuka is at hearing that Seimei was a bad and violent person, he doesn't take his words back, but he does apologize for upsetting Ritsuka and offer to comfort him. At this point he decides that Ritsuka is very different from Seimei and he can start to like Ritsuka. He then starts addressing Ritsuka without an honorific... and soon after, Ricchan.
"Ritsuka, you and I are kindred spirits. I gave up on Soubi too. But giving up doesn't mean turning your back on him, it's just acceptance."
Aoyagi SeimeiKio does not hide his hatred for Seimei from anyone, including Ritsuka who he lets know immediately upon meeting, that he hated Seimei.
Kio has an extreme hatred for Aoyagi Seimei and continuously reaffirms his opinions throughout the story, though soon warms to Seimei’s younger brother Ritsuka when he realizes both how pure the boy is and that Ritsuka is responsible for Soubi becoming ‘human’ again. Although he’s pleased with this change, however, he is also very jealous of the relationship Ritsuka and Soubi have, and often calls Soubi a pervert or warns others of his Lolicon (sexual attraction to younger girls) behavior.
Kio was kidnapped by Nisei and held hostage by Bloodless. while Soubi and Ritsuka were at the Seven Voices Academy. Kio was used by Seimei as leverage to get his own fighter, Nisei, back after he was taken captive during Beloved’s attack on the school. While in Bloodless’s custody Kio was baited and belittled but the thing that would stick with him most during this incident was not the cruelty he was treated with. While held hostage, Kio received a visitor who he remarked could be mistaken for his twin. She then refers to him as “Big Brother Kio.”
[Note to future Jess from past Jess - Expand on Shikiko section and Shieko section]
Kio is stunned by this encounter and upon being rescued from capture he retreats to the Kaidou household. A wealthy home that is only for the women in his family. Kio goes to seek advise of his daughter, Shikiko, a girl between the ages of ten to sixteen without ears (whom Kio must refer to as Shikiko-san.) Kio asks if he has a sister and is told that it was before Shikiko’s time.
While visiting Shikiko’s mother, a quiet woman named Shieko who Kio speaks to from his knees, Shikiko muses on her father’s “weakness” and how he must be kept safe.
- Kio is almost never seen without a Chupa Chup, a type of lollipop produced in Spain that comes in a large variety of flavors.
- He hates the sound of a lollipop being bitten.
- It takes Kio (an expert) 10 minutes to finish a Chupa Chup.
- Kio'd favorite Chupa flavor is Pudding, and then Cola.
- Kio has 14 total piercings and did them himself.
- Kio notes that when his daughter was born he had no knowledge of it.
- Kio either was kicked out (his story) of his family home or ran away (Shikiko's story).
- In volume one, Kio alleges that he is Soubi's wife to his classmates.
- After Seimei, Kio's phone number was the second ever to be entered into Soubi's phone.
- Kio has part time work as a nude figure model for drawing.
- Makes no appearances in vol 4.
- Before having hotpot with the Zeros and Soubi, Kio offers to return a key to Soubi's house that he had borrowed and quote, "no longer needed."