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He has a large horizontal scar stretching from cheek to cheek, crossing the bridge of his nose. Ken uses his Channels by inputing different animal teeth cartridges over his own which modify his physiology to reflect that of the animal he chooses. Despite not having a cartrige in, he is always seen with sharp canines. When doing this, a small image with the face of the animal will appear on his cheek. He is almost always seen wearing a green Kokuyo Middle uniform but for his casual attire, he wears a gray-blue hooded jacket over a yellow shirt with brown pants.
He likes to tease and belittle others, but he himself is very eccentric and over-confident. This causes him to clash with the calm, grounded Chikusa. Occasionally, during speech his tongue will pop out. He often speaks out of turn and as a result, is punished by Mukuro. It is shown that he demonstrates great loyalty towards Mukuro and will listen to all his orders even if it would mean sacrificing his own life. He is known to show a somewhat softer side where Chrome is concerned. Though he acts very harshly towards her in person, he is constatnly worried about her well-being and happiness, as demonstrated when he went shopping specifically for things that "would make her happy". Whenever his concern for her is acknowledged (usually by Chikusa), he denies it almost instantly and tries to play it off.
Appearances in other media
He appeared in the Hidden Bullet Novel series. He appeared as a minor character in the first novel Hidden Bullet: Mukuro's Illusion, when Mukuro took over Kokuyo Land. And, also in the second novel, chapter one, Hidden Bullet: 2X-Fiamma: mono.CHROME, which tells how he and Chikusa first met Chrome: he and Chikusa went to Japan as ordered by Mukuro to find "the other me" in their dreams. Due to Ken missed Mukuro so much, he started to imaginating a pile of pineapples on the market 'talking' to him with Mukuro's signature laugh, making Chikusa commented that he had gone crazy. Ken retorted this and after some arguments, he left Chikusa and then fell asleep at Namimori Park. When he awake, he's surprised when he realized that he slept on someone's lap, who turned out to be Chrome who's still Nagi at time. When his stomach growled because of hunger, Nagi fed him an apple, which he accepted and tearfully ate as it reminded him the time when Mukuro also gave him an apple on the night they were running away from the Estraneo lab.
In the Reborn! artbook Colore; it's revealed that he often secretly wears Mukuro's jacket uniform, eats his ham from his fridge, and eats his ice cream in his freezer, which are all supposed to be forbidden. Unfortunately for him, Mukuro already knows all of this and is ready to punish him.
In the Chrome Saw It! A Happy Day at Kokuyo Land! Drama CD as a side character in Chrome's flashbacks and when he and Chikusa went to pick Chrome up form Tsuna's house. Despite Tsuna's protests about the fact that Chrome was changing, Ken kept on yelling for her to come out. When he suddenly says 'the pineapple-head inside', Mukuro switches with Chrome and uses his First Realm on Ken.
Lastly, he appears in the eight Drama CD "Namimori Radio - ON AIR!", where he's hosting one of Vongola's radio corner called "Ken Ken Paw's Corner". During the air, he constantly compares Mukuro's hair with pineapple, causing him to be nearly had his hair cut by Mukuro and nearly beaten up by him with the fourth path until Ken says it was a joke. However, in the end he is eventually punished by Mukuro when Chikusa reveals that Ken only feeds Chrome with chocolate snacks, angering Mukuro who uses his fifth path against him, and Ken's cries was heard as Mukuro cut the radio connection, ending the corner.
Weapons and Abilities
- Channels: Ken utilizes his Channels by inputting sets of animal teeth cartridges over his own, which modify his physiology to reflect that of the animal.
- Sun Ring: In the Final Future Battle Arc, Ken is briefly shown wearing a Sun-attribute ring while battling Zakuro.
- Ken doesn't bathe daily and claims to only take a bath once a week or a month. He even stated once in Drama CD that he rather being punished by Mukuro than being forced to take one.
- His favorite snack is peppermint-flavored gum.
- His favorite animal is bird because he thinks it looks delicious.
- His hobby is touring candy shops, fighting, and playing video games.
- He and Chikusa apparently know where Tsuna lives by tracking Chrome's scent as they went to pick up Chrome when Tsuna brought her over to his house to dry and change her clothes since Lambo caused a bucket of water, meant for Ken, to spill over her.
- Shusei Kagari from Psycho-Pass bears resemblance to Ken, as both characters were designed by Akira Amano.
- Despite having his own bed at Kokuyo Land, Ken prefers to sleep on the floor because he thinks that the bed is too soft for him to stay still.
- In the manga, he has the Opossum Channel, but he didn't have this in anime. He also had a wild boar channel in the Drama CD which was used to track Chrome's scent when he and Chikusa were looking for her and Kangaroo Channel in Hidden Bullet Novel.
- He has a habit of ending his sentences with "-byon."
- Because of his fangs, he has a lisp and can't say "shut up" and "why" properly.
- In Hidden Bullet Novel: mono-Chrome, it's revealed that he was the one who cut Chrome's hair into pineapple shape like Mukuro.
- A running gag in the Drama CDs, he is always compared to a dog and Ken would always retort that he's not a dog just because his name literally means dog (unaware that it was his behavior that caused him to be compared like one). Ironically, in several occasions in the series, dog ears and tail appears from him as comical effect. Mukuro also once used a command "Kanna, Ken" to him, a command that usually use for dogs in Japanese.
- His Fandom Shorthand is 14.