Roxas

In Kingdom Hearts II, Roxas is introduced as a kid living in Twilight Town. While there, Roxas begins to see memories of Sora's adventures in dreams, and also encounters Axel, sent by the Organization to either rescue or kill him,[12] and Naminé, who tells him he is Sora's other half. Eventually, Roxas is led to the old mansion by Ansem the Wise, where he makes his way to the basement and sees Sora's comrades, Donald Duck and Goofy, sleeping in suspended animation. It is then revealed that Ansem the Wise placed Roxas in a digital replica of Twilight Town and erased his memory and implanted false ones to hinder them from Organization XIII. When he reaches the room where Sora is being kept asleep, Roxas rejoins with Sora, allowing him to wake up. Sora later learns that Roxas is his Nobody, a being created when Sora briefly lost his heart during the first game. Xenmas brought Roxas to Organization XIII as he could wield the Keyblade, weapon which would allow them to capture hearts. At some time, Roxas betrayed the organization and Riku, one of Sora's friends, captured him to help Sora wake up. Roxas makes two appearances near the end of the game. The first is a mental battle with Sora, and the second is with Naminé before escaping from the Castle That Never Was. In the Final Mix version of the title, Roxas' fight against Sora was expanded, making him a boss character; The staff worked hard in order to make it entertaining for gamers.

In Kingdom Hearts 358/2 Days, a prequel to Kingdom Hearts II, it is explained Roxas' life with Organization XIII. Unlike the other Organization members, Roxas lacks memories of his previous life, due to the short time Sora had spent as a Heartless before being restored to his original human form; however, in exchange for that, he gained a capacity for emotions. During Roxas' time in the Organization, he is placed under Axel's watch, and they eventually become friends. After Axel is sent to Castle Oblivion, Roxas is entrusted with Xion, another Keyblade wielder, whom he falls in love with before he falls into a month-long coma at the same time Naminé begins to restore Sora's memory. Awakening and attempting to spend time with his friends, Roxas begins to react to Sora's memory restoration as he starts to question why he uses the Keyblade and doubt the Organization's motives. When he discovers that Xion is a Replica of Sora created by Xemnas, and feeling betrayed by Axel hiding this from him, Roxas is compelled to defect from Organization XIII to find answers and hopefully meet Sora. After doing so, he encounters Xion, who tries to attack and absorb him so that she would become the "real" Sora; however, Roxas defeats her and gains her Keyblade. The death of his lover, coupled with full knowledge of how evil and deranged Xemnas truly is, only strengthens Roxas' resolve as he decides to take out Xemnas himself and release Kingdom Hearts. However, Roxas is confronted by Riku who knocks Roxas unconscious.

A virtual representation of Roxas also appears as a boss character in Kingdom Hearts coded, game in which he confronts a virtual representation of Sora. He cameos at the end of Kingdom Hearts Birth by Sleep, where he is shown with Xion and Axel eating sea-salt ice cream in Twilight Town. All three look into the sunset and utter Sora's name. Roxas also appears in the Shiro Amano's manga and Tomoko Kanemaki's novels which reprise his role in the video games.