In the manga and anime Rurouni Kenshin, the secondary character Himura Kenji is the son of Himura Kenshin and Kamiya Kaoru after they wed at the end of the Jinchuu Arc.
In the manga time line, Kenji is a genius at swordsmanship. By age 15, he is a master of both Kamiya Kasshin Ryu and Hiten Mitsurugi Ryu. This genius leads Kenji to become a rather twisted individual. The author, Nobuhiro Watsuki calls him "more cynical than Saitou and more selfish than Shishio". Kenji's views on swordsmanship contrast sharply with his parents, causing a schism to form between Kenji and his parents as he matures.
Eventually, Kenji will come to blows with Myoujin Shinya, the son of Myoujin Yahiko and Sanjo Tsubame. Shinya is Kenji's arch rival and like Kenji, is a master of Hiten Mitsurugi.
In the time line of the Seisouhen OVA, Kenji grows up resenting his father's extended absences and his mother's constant depression. At age 15, Kenji leaves Tokyo and heads to Kyoto to study Hiten under his father's former master, Hiko Seijuro XIII. Hiko teaches Kenji some battoujutsu, but doesn't teach him the more advanced forms.
After Kaoru falls ill with Kenshin's disease, Yahiko shows up on Hiko's mountain to try and convince Kenji to return home with him. Kenji declines, saying that he must learn what true strength is and to surpass the legend of his father. Yahiko gives Kenji the Sakabatou for the night in the hope the young man will at least try to understand his father. Kenji holds the sword and reflects on his father's extended absences and intractable sorrow.
In the morning, Yahiko and Kenji face off in a duel. Kenji attacks Yahiko with acrobatic grace and displays his genius heritage. Yahiko even admires how proficient with the blade Kenji is and how naturally it comes to him. However, Yahiko is armed with 15 years of experience and the desire to protect that he learned from Kenshin. Channeling these into the blade of the Sakabatou, Yahiko knocks Kenji's blade from its hilt and takes Kenji down with a strike to the shoulder.
Yahiko passes the Sakabatou on to Kenji for his genpuku or 15th birthday ceremony. Kenji then returns to Tokyo with Yahiko to bid his mother goodbye before she dies.
Time passes and at the end of the movie, we see Kenji who is now clad in gi and hakama like his father used to wear and carrying the Sakabatou. He sets out from the dojo with a girl by the name of Raikoji Chizuru by his side. Chizuru looks a lot like Kaoru, leading many fans to think that Kenji suffers from an Oedipal complex. As they pass the sakura field where Kenshin and Kaoru died, Kenji stops and reflects.
Chizuru asks Kenji what's bothering him, but Kenji dodges the question and compliments Chizuru's blue hair ribbon. He then says that they will live happily together as the two walk down the path.