Tsukasa is a Wavemaster and the main character. He is a young silver-haired boy clad in grey robes, At the start of the series, he is seen waking up to find himself in a dungeon in The World, but he has no idea why he is there or who he is. Not much time passes until Tsukasa discovers he is trapped in the game, unable to log out, while his real body is in a coma. He is initially depicted as a cynical loner who tends to avoid others as much as possible, but at the story progresses he begins to warm up to Mimiru, Bear, Subaru, and others. In the real world, his name is An Shouji, and he happens to be a girl. She was raised by her father after the death of her mother, and was physically and mentally abused by him. His abusive behavior also distanced her from her gender: he treated her like a boy, refusing to allow her to use feminine products and basic hygiene products. There are also subtle hints that her father is an alcoholic. After awaking from her coma, Ryo Sakuma, the player behind Bear, becomes her legal guardian and allows her to go to a boarding school. She meets with Mariko, Subaru's player.
Tsubaki is Mizuki's lover. She claims that Mizuki used to be a sweet man, but ever since he got involved with Orochimaru, her relationship with Mizuki has faltered. When he escapes from prison she is able to help catch him. After she interrogates Mizuki about having a grudge against one who put his life on the line during Orochimaru's attack, Mizuki knocks out Tsubaki, who he apparently does not love anymore. After Mizuki was defeated, she mentioned to Iruka that she may have to face whatever consequences for her involvement with Mizuki. Source: Narutopedia
Tsubaki is a fiery male spirit who is the only Shun Shun Rikka capable of direct attack. He often strikes anyone who gets on his nerves (including Orihime). Because he is primarily focused on attacking, he is vulnerable to counter-attacks and has been injured several times. The stronger Orihime's anger and killing intent, the more powerful he becomes. However, Orihime's timid nature limits his overall power and has contributed to his injuries in the past. At one point, Tsubaki was killed by the Espada Yammy Riyalgo, who crushed Tsubaki into tiny pieces. Orihime was distraught by this, and since the pieces were too small to find, she couldn't bring Tsubaki back. But due to meeting Hachi, who said Orihime's powers were similar to his, Tsubaki is restored by Hachi despite having no pieces of him
Tsukado is a master swordsmen of an unnamed clan who had a vendetta against a man that killed a relative of his, Shikazo. Tsukado was chosen with the task of avenging him by the killing the man who killed him, Katazu. He failed 34 times to defeat him. One day, Team 7 meets Tsukado and seeing his poor revenge skills, Naruto decides to train him. Though his lessons were unusual, he managed to get the upper hand in his next fight with the killer. Naruto stops the fight after noticing Katazu's sword wasn't even sharpened, saying he couldn't possibly kill his relative. He says that it was his twin brother, Kageki who killed his relative but it was an accident. Since then, he has been taking his brother's identity. The Kanabun Gang, who were profiting off their fight, try to get the two to fight again but with the help of Team 7 manage to chase them out of town. Tsukado is shown to be able to use chakra flow when using his sword. (source: Narutopedia)
Tsubaki appears in the second chapter of Bloody Junkie when Shouta tries to tell him that someone has died, despite the viewers protests that he may be the killer. He attempts and fails to kill Shouta in this scene with a pendant knife but is scared off by a firecracker that he thinks is a gun. Tsubaki's starter weapon in this game was a rubber ball, however it is stated that he is a 'Repeater' and has won the game before. In total he has 3 known weapons including the screwdriver he stole from a dead man. He has joined the game with the full intention of winning and even calls it a form of tag.