Story of Kintaro
Kintaro was known for his tremendous physical strength and loyalty. Kintaro's mother was one of the mountain spirits known as Yamauba. She has also been described as a mortal, devoted to her warrior husband who was wrongfully banished from court. As Yama-uba, she was a posthumous child and was brought up in a mountain retreat, with only his mother and animals as his companions. Apparantly he was a beautiful child, with golden skin. He was, as a small boy, strong to the extent of being able to uproot trees with only one hand.
To wrestle with a bear was merely an exercise, involving no danger for the child. Apart from his strength, Kintaro showed a certain wisdom in his childhood, for he used to adjudicate when his animal friends tussled together to test their strength, though there is no record of Kintaro being an onlooker of an animal fight to the death. His strength was eventually discovered and he was taken to the court at Kyoto where, it is believed, he eventually became a retainer of Yorimitsu, also known as Raiko, an early leader of the Minamoto clan. Eventually Kintaro vindicated his father's name and in manhood became a warrior too.
Source: Japanese Mythology, written by: Juliet Piggott
Relevance to Urusei Yatsura
Ten's little friend Kintaro is based upon this childen's story hero. Apart from the fact that he comes from space, UY's Kintaro looks exactly like he's discribed in stories. The Kintaro of storybooks is also referenced many other times throughout Urusei Yatsura. Especially with Shinobu who has a similar hairstyle and has his superhuman strength.