Yuichiro has shoulder-length brown hair in a ragged style with a full fringe as the side bang at the right to cover his right eye and black eyes.
When he works as the shrine apprentice, he wears a white traditional kimono shirt, light blue hakama, and white sandals.
When he goes with Rei during their shopping spree, he wears a light blue denim jacket with an openly white short-sleeved button shirt with a black short-sleeved turtleneck shirt, matching pale blue denim pants and black shoes.
In Episode 99, his casual attire has minor changes and his denim jacket and pants are now dark blue and his button shirt becomes pale yellow and during his decision to leave Hikawa Shrine and became victimized by Kaolinite's Daimon, he is not seen without his denim jacket and his black shoes are replaced with brown geta sandals and carries a brown and white duffel bag.
In one episode when he goes to Rei's grandfather, he was seen wearing a gray formal suit.
He made his first appearance in episode 30, sleeping on the steps in front of Hikawa Shrine. When he woke up, he saw Rei Hino and immediately fell in love with her. Due to his love, he begged Rei's grandfather to allow him to become an apprentice. Later, Rei's grandfather began an intensive training program for Yuichiro, telling him that becoming a Shinto priest is tough work, and you can't do it with a soft attitude. Although the training was very difficult and physically exhausting, he was very determined to continue working hard.
In episode 38, Yuichiro revealed that he was actually from a very wealthy family. Usagi and her friends wanted to visit the Moonlight Course ski resort, and Yuuichirou offered to let them stay at his parents' home near the resort since his parents were away at their vacation home in Switzerland. Rei asked why someone from such a rich family would choose to work at the shrine, and he told her that he wanted to better himself. During this episode, Yuichiro attempted to protect Rei from a youma's attack, only to be knocked unconscious in the process. Although Rei later called him a "useless idiot," she did kiss him on the cheek while he was unconscious.
Sailor Moon S
In episode 99, Yuichiro (believing that Haruka is male) was hurt when he began to believe that Rei and Haruka were dating. Later, he saw Haruka with Michiru and was angry because he felt that Haruka was cheating on Rei. He challenged Haruka to a duel, but she wasn't interested in the fight. Rei overheard the argument and tried to intervene, but Yuichiro misunderstood her and continued believing that she was with Haruka. He decided to leave Tokyo, and the Inner Senshi persuaded Rei to go after him. At the train station, Kaolinite appeared and extracted his Pure Heart Crystal, knocking him unconscious. After quite a battle (of which he was unaware), Rei took him home and took care of him.
Sailor Moon SuperS
Yuichiro appeared for one last time in the anime in the SuperS series, where Mamoru was staying at Hikawa Shrine when his apartment was being cleaned. He became extremely jealous, thinking that Rei had a crush on him. After Sailor Moon and the group saves Rei who was victimized by Tiger's Eye. Yuichiro apologizes to Rei due to her grandfather's activities as the latter becomes irritated and reluctantly accepts his apologies.
In Episode 152, Yuichiro was mentioned by Rei and stating that he has taken a vacation as she handles all of his chores.
- In the DiC English dub, he speaks in an Australian accent in a surfing dude language. But on Cloverway dub, he speaks in a slight North American accent.