He used to be very shy and reserved, always hiding himself behind Kounosuke. Now he isn't shy at all and is becoming a follow-up to his brother. He has a cheerful personality because of his brother's influence. Recently he has been becoming less dependent on his brother. This seems to make Kounosuke a little lonely. When he sees Hiroyuki Nishimura for the first time after his arrival in Minasato, he doesn't recognize him instantly, by the fact he was a child at the time of his leaving, but he remembers a few moments later, especially the troubles that Hiroyuki and Kounosuke used to make.
Yukiharu is a serene and responsible person, the total opposite of his brother, what gives him an older look, contrasting his real age. He's enjoyable and likes to play outside along with his friends. His morale can be severe sometimes, but kindness is his major expression. As a dependable person, he is discontent with his brother's carefree personality, but his preoccupation demonstrates his fondness.
Yukiharu wears a white sleeveless T-shirt, stamped with a surfing figure, detailed with red and blue. His low parts are not shown.
His body is very similar to Kounosuke's body: yellow brown fur and a beige coloration on the chest. His ears and tail's ends are dark brown, and his eyes are golden.
He is a noticeably short and overweight character and unlike Juichi or Tatsuki he has no discernible muscle.