Tentang
A man born with super human strength that can resist even bullets, similar to Kenshiro of Hokuto no Ken. He also heals much faster than a normal human. He was separated from his younger brother Nachi since childhood and was adopted by the Saiga family. He has a scar in the shape of the Star of David on his right hand.
This scar is also a sign that he's destined to overthrow his real father.
Riki's mother was executed for poisoning 13 infants, and Riki and his brother Nachi was carried away from the prison by a caretaker before they were dealt with punishment. Zhāng Shàn-Guǐ stopped Riki from committing suicide infront of his mothers grave and became Riki's sifu in the ways of Qi Gong.
Riki's friend, Keiko, was hit by a car - although the wounds weren't life-threatening, she later fell into a coma in the hospital due to low-grade painkillers, which was opium supplied by South Port gang. This lead Riki to murder the gang leader which sent Riki to jail.
He keeps the 5 bullets that the Yakuza shot him with in his chest as "souvenirs".
After Riki escapes jail he searches for his brother Nachi.