- "Ryuki, promise your grandpa that you'll kill all the Worms. Those pests must be exterminated. I'll teach you how to kill them."
— Gaoh Mukaku's request to his grandson, Gaoh Ryuki
Mukaku was a powerfully imposing individual, with a bulky muscular frame and an obviously battle-worn body and face littered with scars. He had a mat of hair atop his head, thick distinctive eyebrows, cauliflower ears and thin stubble above his lip and on his chin. Gaoh typically wore dark bottoms and wrapped his stomach in bandages (essentially creating a rudimentary haramaki) with a loop of bandage wrapping over each shoulder.
In Ryuki's memories of him, Mukaku was much older than when he was training the Tokita Niko's. He had grown out a goatee, and his eyes had grown weary, either from age or something else. His two scars and eyebrows remain very much the same however.
While his personality is almost completely unknown, it can be inferred that Mukaku was extremely driven given that his desire for unification was not quelled even after over 30 years of trying. He is also inferred to be a good teacher, instructing numerous children in martial arts all alone.
It's implied that he has a certain hatred for the Worm. The exact reasons are currently unknown, but evidently strong enough to make his grandson Ryuki promise that he will kill them all.
Gaoh Mukaku made a sudden appearance in history when he attempted to unite the Inside all on his own through force. However, despite constant domination in battle for thirty years, he found himself nowhere closer to his goal, so he chose to pass on his fist and his dream to the next generation instead. With the help of his friend Shimochi Kazufumi, Gaoh rearranged his style into one more useful for the modern day, and adopted a number of orphans, naming them all Tokita Niko, after two of the districts of the Inside. His purpose in doing so was for the Niko's to all act independently in the same name, to build up a legend.
While the Niko's were initially successful, the resistance against them grew more fierce, until eventually Gaoh decided to pass on a secret technique to them in Gakigahara Forest. However, in this forest, most of the Niko's were murdered and the rest were scattered. Gaoh himself vanished without a trace.
At some point he raised his grandson Gaoh Ryuki, teaching him the Gaoh Style and made him promise to kill all the Worms he would encounter in his path, even teaching him a special technique using the principles of Armorclad.
Power & Abilities
Mukaku was a powerful martial artist who never was defeated in battle, despite battling constantly over thirty years using the Gaoh Style. He later created the Niko Style and can be assumed to be masterful in its usage.