Ramon Kasumi, later known as Ryūken, was born the younger half-brother of Kenshiro Kasumi, sharing their father Tesshin Kasumi but having different mothers. In his youth in Japan, he protected Aya Kitaōji from hired thugs and then served as bodyguard for Pan Yuling, shielding her from the Tàihú Bāng gang during her stay.

His deepening connection to Hokuto Shinken culminated in a successful battle against Kōryū for the succession rights. He ultimately became the 63rd successor of Hokuto Shinken. Later, he adopted and trained four disciples: Raoh, Toki, Jagi, and Kenshiro. After selecting Kenshiro as the next successor, Ramon attempted to seal Raoh's rebellious fist but suffered a heart attack during the confrontation, allowing Raoh to kill him. Kenshiro remained unaware of the truth initially; Toki revealed Raoh's role during Kenshiro and Raoh's first battle.

Ramon played a pivotal role in naming his nephew, the protagonist. Present at Kenshiro's birth in 197X, he named the child after his older brother, Kenshiro Kasumi, noting both bore a Big Dipper-shaped birthmark. He regarded his older brother as the "Strongest Hokuto Shinken warrior," comparing his might to "the blue sky above."

In the *Regenesis* storyline, Ramon's legacy resonates through the broader narrative of Hokuto Shinken's history and succession line, his foundational actions and relationships continuing to influence the franchise's events and characters.