Yosuke is a shinobi of Konohagakure from the famous Senju clan of Konoha. The Senju clan was known allover the world as one of the strongest clans and being related to the Sage of the the six paths as the clan is descended from the youngest son of the sage "Senju". They inherited the body of the sage, which gave them superb physical prowess. One that surpassed all normal means. Yosuke's story begins in Konoha on the day of his birth. He was born after the fourth shinobi war with some years. His father died after the pregnancy of his mother with two weeks as he died on a mission assigned to him. His mother died during his birth and he was born an orphan who had no father or mother or even a home to go to. He was then adopted by a man from the Senju clan. He was a rich man who knew Yosuke's father and he decided to adopt his son as a reminder of his old friend and a favor to him even after his death. Not to mention that he felt sorry for Yosuke who was born an orphan.
That man was the one who gave him his name "Yosuke" as it reminded him of his grandfather so he decided to pass it upon this child that he adopted. Since he wasn't married, he didn't have children and that was the secret for his love to Yosuke, he saw in him the son that he never had and he felt like a father. This man's name was Kazuki. He built a strong bond with Yosuke as he loved him greatly and enjoyed watching him grow. He wanted to train him to be a strong shinobi who would be able to carry on his legacy and his father's legacy. He was a fun old man who was always cheerful and loved to play around. He was a pervert as well as he always tried flirting with young women, despite being in his sixties.
When Yosuke was three years old, he had already learned how to talk and walk. He could walk before even reaching one year of age as he showed abnormal strength for a child. He seemed to be strong despite being a child as he showed ability to walk faster than any other ordinary child, which was an indication of his physical strength since being young. Kazuki started training him in using chakra since he was four years old. He started showing him how to mold chakra and the basics of chakra control. He showed him by explaining the concepts of chakra and how it works. Yosuke showed deftness in learning about them with ease and he started using chakra bit by bit until he was able to walk on walls after two months of practice. It took him a while to get it down since he was very young for such training.
Physical Prowess & Life Force