|Gallery | Relationship | Quotes|
|Duel Monster statistics|
|Affiliation||Den Academy's Duel Club|
He loves Dueling, but he’s not too confident about his skills and has never Dueled in LINK VRAINS. He is also a fan of Playmaker. He's enthusiastic, passionate, and tries to be friendly with Yusaku. During his observations, Yusaku pointed out that Naoki cannot stand being alone.
One day, Naoki noticed Yusaku asleep after class had already ended and introduced himself, noting that Yusaku has no friends. He was upset that Yusaku didn't remember him, as they had been classmates for over a month. Naoki tried to befriend Yusaku and showed off his new Duel Disk, only for Yusaku to criticize Naoki's lack of Dueling talent, but also pointed out that Naoki had good intentions. Naoki got upset at Yusaku's remarks and stormed off, telling him to Duel by himself. Later he went to watch Duels at Link VRAINS and was scared when The Knights of Hanoi attacked, and was surprised when "Playmaker" appeared.
Naoki asked what the Duel between Playmaker and The Knight of Hanoi was. A young man wearing an apron answered him that this was called an "Speed Duel". He was surprised that Playmaker used the Cyberse type and was happy when Playmaker attacked Hanoi's "Cracking Dragon" but became worried when the Dragon survived to the attack and Playmaker fell from his D-Board. After that Blue Angel saved Playmaker, Naoki cheered him to protect Link VRAINS. He worried when Playmaker is sucked into a tornado within the Data Storm and was relieved when Playmaker won the Duel. A few days later, in the classroom, he asked Yusaku if he had seen Playmaker in action before, Yusaku answered that he had not seen him. Naoki shouted at Yusaku if he considered himself a duelist. He told him that he checked Link VRAINS over to see if Playmaker was going to show up again on his electronic note pad and was horrified to see a Knight of Hanoi. He showed the knight to his classmates and was suprised when Yusaku disappeared.
At the Duel Club, he noticed that that Yusaku was wearing his Duel Disk, inferred that he wanted to join the club, but insisted that it was no place for someone with no interest in Link VRAINS. Club president Hosoda opened the door from inside to reprimand Naoki for making so much noise, but allowed Yusaku to join, stating that new applicants are always welcome. After all the club members introduced themselves, Sato showed off his new Duel Disk, with Yusaku feigning interest about its new AI program that assists in Dueling. Aoi commented that Yusaku knew a lot, and Yusaku said it was only because Naoki bragged about it, but he hadn't realized that everyone in the group had the new Duel Disk. Naoki took exception to this, and replied that Aoi's brother Akira was a big shot at SOL Technology and gave the Duel Club members the new model first, prompting a stern look from Aoi. Aoi noticed that Yusaku's Duel Disk was a card-loading model, the same as Playmaker's.
Naoki speculated that Yusaku was copying Playmaker, but lamented that Playmaker was behind the times using such an old model. Aoi then asked to see Yusaku's Deck. After Aoi looked at the cards, she tried to give the Deck back, but Naoki snatched it up and started laughing about how lame the Deck was, to which Hosoda rebuked him for insulting it. Naoki then gave it back to Yusaku and apologized, but Yusaku told him he was right. After he listened to Hosoda gave a lesson on the differences between Speed Duels and Master Duels. The next day in the classroom, Naoki was suprised and pleased to watch a Speed Duel between Playmaker and Blue Angel. When he saw Blue Angel summon "Dark Angel", Naoki got scared and screamed, causing the teacher to scold him and as the lesson was going on.
|Main||Aoi Zaizen • Go Onizuka • Yusaku Fujiki|
|Den City||Aoi Zaizen's robot • Den City orphanage owner • Eagle • Emma Bessho • Frog • Go Onizuka's manager • Hosoda • MC • Naoki Shima • Pigeon • Roboppy • Shoichi Kusanagi • Tanaka • Sato • Suzuki|
|SOL Technology||Akira Zaizen • Bishop • Hayami • Isomaki • King • Knight • Kitamura • Pawn • Queen • Rook|
|The Knights of Hanoi||Dr. Kogami • Revolver • Specter|
|Other characters||Shoichi's brother|