|Dub Name||Kaz Walker|
|Game Debut||Danball Senki (PSP)|
|Anime Debut||Episode 01|
|Appears in||Game, Anime, Manga|
|Voice Actor||Daisuke Namikawa|
|Age||13 (debut), 14 (W)|
|Occupation||Student, LBX Player|
|LBX:|| Warrior, Hunter, Fenrir, Achilles Deed|
Egypt, Gladiator (rental)
|Achievement(s)|| Angra Visdas Best 4|
2050 Artemis Participant (Ban's Team)
2050 Akihabara Kingdom Runner-Up (Jin's Team)
Kazuya appears with kinky, ginger hair tied to the back as a ponytail, and has dark, cerulean eyes. He wears a baby blue jacket, a white dress shirt with its collar popped and red tie, a pair of black pants and black dress shoes.
In his first appearance in W, he is shown wearing a cyan polo tank top, two dress shirts (white and pale blue) with both collars popped, black pants and black dress shoes. He also ties his ponytail a bit higher. After rejoining with Ban and the others, he changed his hairstyle from ponytail to stand-up dreads sporting a green headband. He wears black tank top, khaki pants, green armbands, pair of black boots and looks more muscline. He also has a scar-like mark on his right cheek.
In WARS sketches he has less dreadlocks and is seen wearing grey t-shirt, black vest, green pants and googles on his neck.
In original series Kazuya appears to be friendly to those around him, but also unconfident and gives up very fast when it comes to matters too difficult to deal with. Thus he will never hesitate to act harsh to those who attract harm towards his friends. This behaviour was shown towards Jin Kaidou when he was siding with his adopted grandfather's evil agenda. But the latter will eventually subside as Jin proved himself as one of Ban's comrades.
In W series Kazu shows much less personality than he did in the original series and after rejoining Ban and the other variors usually has no impact on the flow of the story. He just fights along his friends.
Season 1Aoshima Kazuya, also known as Kazu, is shown in the season in an LBX shop with Ban and Ami and is played out through the season as one of Ban's good friends to battle with. Things get a little more serious when his LBX Warrior got destroyed by Hanzou Gouda when the group of friends were trying to get the Achilles armor back from him. He got very depressed about it. Then he started looking for a new LBX, but somehow this one stall he went to during the episodes was a trap, ending up being controlled by Innovator and using Egypt in a battle against Ban, who wins the battle, getting Kazu back to normal. Later, the group of friends were called by a mysterious man to do a mission related to the president who was actually about to get assassined by Innovator and somehow it ended up getting Kazuya to recieve a new LBX named Hunter. Also the only time he ever lost was during a tournament and lost to Jin Kaidou.
Season 2In Episode 1 (W), he and Ami were waiting for Ban in TokioSIA to watch the Tiny Orbit's latest anouncement. All off a sudden, the event got interuptted when the brainjacked LBXs ramapaged TokioSIA, and Kazu with Ban and Ami fought against them. Unfortunately, his Fenrir got destroyed and Kazu was gassed and kidnapped by Detector along with Ami. While Ami has already been saved by Ban and his crew, his location is yet unknown.
In Episode 29, Kazu reappears as a Slave Player in Camberlin with a new appearance, only to turn against Asuka, breaking-over her Vampire Cat thus freeing her from enslavement. It was revealed that he was brainjacked, until an accident short-circuited his collar, thus he was not controlled like the others. Understanding the masked man's identity and Detector's true nature, he assisted the masked man from his own will, all the while assisting Ban against the true enemy.
Throughout the rest of the series, he along with his friends attempt to try and stop Hiyama Mami's plan to take over the world, which she thought was her brothers, Lex's, dieing wish. Ban and Hiro managed to stop and defeat her LBX Zeus and then convinced Hiyama that Lex's dieing wish was not to destroy the world. After they completed their mission, they all went back to their regular lives. Kazu along with Ami and Asuka participated in a special lecture on LBX's at the assembly stage at 15th Street's park, to try and promote everyone to use LBX's and that they're safe and fun.
After that, there was news about a new LBX rampage, and a strange LBX was shown at every scene from the rampages. Soon after they found out it was Mizel's doing, and was the one controlling the LBX's.
In the crossover movie, he appears along with the whole team to try and stop the LBX invasion controlled by San in the Holy Road stadium. After Ban, Hiro and the others rescue Fran, he and Ami disappeared because Fran erased them when Ban and Hiro walked first, leaving Kazuya and Ami to walk behind, giving Fran time to erase them.
- Kazuya's new facial appearance in the W season, resembles Crow Hogan from Yu-Gi-Oh! 5Ds.
- It was never explained why Kazu changed his image during W season.