TV-Series
Description
Sakaki Shio, infamously known as the "100-Dan Street Brawler of Karate," is a primary martial arts master at the Ryozanpaku dojo. He presents a tall, heavily muscled frame with tan skin, short eggplant-colored hair, and a distinctive horizontal scar across the bridge of his nose from his late teens. Typically clad in a brown leather jacket, blue jeans, and bandages wrapped around his forearms, he frequently destroys his upper clothing when angered due to sudden muscle expansion. During training, he wears a traditional karate gi.

Personality-wise, Sakaki projects an intimidating aura, often unintentionally frightening others despite attempts to seem approachable. This contrasts with an underlying kindness and fierce protectiveness, particularly towards his disciple Kenichi Shirahama. Initially opposed to taking disciples, he gradually mentors Kenichi, showing deep concern for his safety and progress, even intervening in his battles against Ryozanpaku's policy. Sakaki exhibits a hot-tempered, arrogant demeanor, frequently gambling and drinking. He harbors intense stage fright, becoming visibly flustered in attention-heavy situations like posing as Miu Furinji's father. His attempts at deception usually fail noticeably. He shares a contentious yet familial rapport with fellow master Apachai Hopachai, frequently engaging in petty arguments. Recurring themes portray him as the "closest to evil" among Ryozanpaku's masters due to his aggressive ki and remarks during combat, though he staunchly adheres to the Katsujinken (life-saving fist) philosophy.

Sakaki's background reveals a complex martial arts journey. Trained from youth by a master affiliated with the lethal Satsujinken-promoting organization Yami, he rejected his master's expectations of using killing techniques. During his competitive years, he formed a fierce rivalry and friendship with Akira Hongo, resulting in 125 mutual wins each, refereed by Suzuki Hajime. This period ended when Yami demanded the trio fight to the death; Suzuki attacked first, seeking recognition as strongest, and Hongo killed him to honor his wish. Enraged by Hongo's adherence to Yami's ideals, Sakaki confronted him, resulting in their mutual facial scars. Hongo believed Sakaki died. Exiled from all karate tournaments for destructive tendencies, Sakaki briefly competed underground, earning his "100-Dan" moniker until opponents fled at his name. He traveled globally, undertaking bodyguard work and joining Christopher Eclair and Mycroft for FBI contracts. During this time, he befriended Colonel Lancelot Grey and his daughter Jenny, drunkenly promising marriage to the latter. Sakaki eventually left the FBI after defeating Eclair and Mycroft for advocating lethal force, returning to Japan for undisclosed reasons. He joined Ryozanpaku as a junior master alongside Apachai and Shigure Kosaka.

As a fighter, Sakaki ranks among the world's foremost karate masters, rivaled only by Hongo. His expertise spans multiple karate styles, allowing seamless adaptation between offensive and defensive tactics—a shift influenced by Suzuki's advice. He possesses superhuman physical attributes: immense strength (lifting cars, launching opponents with finger flicks), speed (outpacing vehicles, dodging point-blank attacks), and durability (surviving high falls unscathed). His potent Dou-type ki disintegrates clothing and knocks adversaries unconscious with a glare. His combat perception enables rapid analysis of opponents' styles and instant counters. He speaks fluent English from his FBI tenure.

Throughout Kenichi's journey, Sakaki plays pivotal roles. He initially refuses to train Kenichi, predicting his death within three days, but relents after Kenichi's loss to Tsukuba, teaching him techniques for a victorious rematch. He later defends Kenichi against masters like Gonzui Kumatori. During the Ragnarok conflict, he bets on Kenichi's victories and prevents Isshinsai Ogata from interfering in Kenichi's duel with Odin. In the Yami saga, Sakaki protects Gauche Wynne from Christopher Eclair, rescues U.S. soldiers with Jenny Grey, and battles Yami members like Cyril Rahman—whose knockout techniques fail against Sakaki's resilience honed by Shigure's "scarier" sleep-talking. His rivalry with Silcardo Jenazad intensifies after Sakaki saves Rachel Stanley, leading Jenazad to seek a death match. Sakaki also faces Yami's armed division, struggling against Mikumo before Shigure intervenes. In Okinawa, he effortlessly defeats Yami's "Spear" core member and tends to an injured Apachai. His most personal arc culminates in a long-awaited duel with Hongo; their battle, observed by Kenichi and Miu, showcases such intensity that their clashing ki threatens bystanders. Jenazad halts the fight by kidnapping Miu, prompting Sakaki, Hongo, and Hayato Furinji to unite in pursuit.