Some TMNT stuff really isn't for little kids.
Murakami Gennosuke is the son of General Murakami, a faithful of the Shirogeta clan. Twenty years ago the head of the clan of Oda, a traitor, was murdered; his widow sent out their followers to find Oda and take revenge on him. In this search, Murakami took his family with him and taught his son Gennosuke the sword. Gen's mother, on the other hand, had to earn money on her family's journey; when she finally died, Gen was bitter to his father, and after he had grown up to a man, he moved his own way. In order to survive, he became a bounty hunter using his sword arts, and his general world-view developed into an opportunistic cynic, although he has a good core deep inside.
More than twenty years later, Gen met the ronin Miyamoto Usagi, at the time when Gen was gradually caught up in his past. The two of them happened to meet Lady Asano Shirogeta, who had never given up her hunt for her husband's murderer. She got into the hands of this Oda, now a city magistrate, and although he saw no reason to stand by her at first, Gen finally resigned himself to her support. Although Lady Asano was mortally wounded by Oda, she still succeeded in completing her revenge on him, and Gen found the old swords of his father in Oda's house, who had faithfully served his mistress until death.
At this time, Gen also sealed a close friendship with Usagi, which was to survive his greed, and although the two never take the same path, they work together as partners, whenever fate brings them back together. In a fight with the blind swordmaster Zato-Ino, Gen lost his nostrils, which in his whim (unlike Zato-Inos, who had lost his nose in a duel with Usagi) did not detriment very much. Finally, Gen had also encountered the Ninja Turtles, when they were summoned by mystic forces to Usagi's and his world to protect a village from the Neko Ninja's imprisonment .
In the miniseries Usagi Yojimbo: Senso, fifteen years in the future, Usagi, Gennosuke and Jotaro joined the Geishu clan and took part in the decisive battle against Hijiki, when suddenly alien invaders landed on the battlefield and begin to ravage everything around them. Usagi and his companions do everything they can to stop the invaders and their superior weapons, but since they can not do anything with swords, they have to rely on their ingenuity and the inventions of Takenoko-sensei.
After the first phase of the invasion, Gennosuke and Usagi's son, Jotaro, embark on a mission to eliminate the crew of the first invasion ship. In this action, Gennosuke saves Jotaro's life, but is killed by the supremacy of the aliens.