Moe Fukuoka is a 15-year-old high school freshman who transitioned to professional wrestling after achieving world champion status in Mugengen-ryu karate at the high school level. She is the granddaughter of the legendary wrestler Great Fukuoka, mentor to Berserk organization president Seiichi Inoba. This family connection forged her long-standing relationship with Inoba, whom she has known since childhood. Despite Inoba's previous offers to train her as a wrestler, Moe consistently declined. Her perspective shifted after witnessing a match between Jackal Tojo and Sakura Hagiwara. Inspired by Sakura Hagiwara's declaration of wanting to become the world's strongest and her passionate performance, Moe abandoned her karate career entirely and joined Berserk to pursue wrestling.

Moe exhibits a cheerful, energetic, and highly determined personality. She deeply admires Sakura Hagiwara, referring to her as "Sakura-senpai," and actively seeks her mentorship. This admiration includes strong emotional investment, evident when Moe teared up during concern for Sakura's retirement match against Blue Panther. Her determination drove her through rigorous training; she requested Sakura as her primary practice partner and became the youngest wrestler to debut for Berserk in the shortest preparation time. During her initiation test—a series of throws demonstrating wrestling fundamentals—Moe persisted despite recognizing significant differences from karate, ultimately succeeding with Sakura's assistance for the final segment.

In the ring, Moe integrates her karate expertise into wrestling, utilizing swift kicks, precise footwork, and rapid movement. Her style emphasizes striking power and agility, enabling competitive performances against experienced opponents like Rio Kazama and Sakura Hagiwara early in her career. For her debut match, she deliberately chose Sakura Hagiwara as an opponent to showcase her progress. The match highlighted her technical prowess, as she pressured Sakura with advanced kicks and punches that belied her rookie status. She also executed her grandfather's signature "Octopus Hold" flawlessly. However, a tendency toward flashy techniques led to premature exhaustion, revealing endurance limitations. A key personal goal during the match was compelling Sakura to execute her "Sakura Special" finisher, which she achieved.

Moe's rapid development established her as a formidable newcomer. She defeated Rio Kazama and positioned herself as a serious threat within Berserk. Her unique background and fighting style distinguished her from other recruits, garnering immediate fan interest. The decision to leave karate initially caused introspection during her debut match, but she resolved to commit fully to wrestling, rejecting half-hearted efforts.