Originally, he was the son of an important samurai of a prominent lady until she was betrayed by a villainous subordinate. Disgraced, she took her entire entourage, including Gen's family, on a quest for vengeance only to gradually slide into utter poverty.
Gen's family shared the same fate with his mother forced to prostitute herself for her family to survive. Eventually she died leaving father and son alone in the endless vendetta. As Gen matured, his father trained him in the ways of the samurai and despite his resentment to his father, Gen excelled in the instruction, becoming a formidable warrior.
Upon reaching adulthood, Gen abandoned his father, wanting nothing to do with his vendetta. Carrying a daisho but with little chance for employment, Gen's prospects looked bleak. However, things improved when he encountered a young man and an attractive woman claiming to need medical attention on the road. Tempted by her beauty, he stopped to examine her injury only to find nothing and suddenly realized that the man was about to backstab him. Gen immediately struck him down and subdued his female accomplice. A pair of woodcutters witnessed the incident and, recognizing the defeated criminals, told Gen that there was a bounty on them. Gen claimed the bounty and suddenly had enough money to eat better than he had in years. With that experience, Gen became a professional bounty hunter who disdained bushido in favor of a cynical mercenary attitude determined never to be poor again.
Eventually, Gen met up with Miyamoto Usagi and the pair struck up a tenuous relationship as they periodically teamed up for major bounties, only to cheat each other at the conclusion of their mutual business. Eventually, the relationship matured into a more trustworthy friendship, and the pair has shared many adventures. One was a final encounter with the disgraced Lady and her betrayer; at the adventure's conclusion, Gen discovered his father's daisho; such a proud samurai would never have abandoned it, which suggests that he is long dead, much to the son's belated regret. In addition, through Usagi, Gen met the street performer/petty criminal Kitsune and joined her on a trek of their own; there is a hint of a romantic attraction between the two, but for now they are merely friends, and have gone their separate ways.
His latest bounty was the fugitive female swordswoman Inazuma, not realizing that she was possessed by Jei; however, after finding one of Inazuma's recent victims, he decided to abandon the search, but not before assaulting a competing bounty hunter, Inukai. However, they evidently both reconsidered and tracked Inazuma down together just as she was going to kill the Woodcutters. At that confrontation, Gen now realized the true situation with Jei. Furthermore, fighting her became more difficult when Gen learned forcefully that the possessed Inazuma can cause him debilitating pain at a distance at will with an old spear wound inflicted by Jei. Eventually both bounty hunters were struck unconscious in battle with Inazuma, but were puzzled why she then departed without killing them. Considering how supernaturally formidable their quarry is, the bounty hunters have decided to call for help to bring her down. To that end, the pair soon meet Usagi and the monk Sanshobo who both insist on joining the hunt. They eventually found Inazuma mortally wounded and while he, Usagi and Inukai held off a horde of competitors, Sanshobo exorcised Jei's spirit out of the swordmaiden, enabling her to die in peace.
Gen in the 2003 Teenage Mutant Ninja TurtlesEdit
Gen, along with Usagi, is a recurring character in the 2003 Teenage Mutant Ninja Turtles series, where he is voiced by Dan Green. Although his character is for the most part unchanged, there has been at least one significant alteration: while he is no longer an avid drinker, he is instead a heavy gambler.
Gen can be seen in the following episodes:
- The Big Brawl, parts 2 to 4
- The Christmas Aliens
- The Real World, part 1
- Samurai Tourist
- Wedding Bells and Bytes
In the "Samurai Tourist" Gen took for a moment clothes that were identical to those Rocksteady, Teenage Mutant Ninja Turtles rhinoceros mutant from the 1987 series.
- Gen lost his horn in a sword fight with Zato-Ino.
- The character is partially based upon "Sanjuro Kuwabatake" (aka "Sanjuro Tsubaki"), a ronin portrayed by Toshiro Mifune in the Akira Kurosawa films Yojimbo (1961) and Sanjuro (1962).
- Gen is skilled at Kenjutsu.
- Quote: "After all, I am your best friend".