He had brown hair and wore the Sankai High School uniform while being a ghost.
He and Sakura's mother, whose maiden name is Miyamae, were members of the Broadcasting Club and had the same taste in music. Much to his joy, she lent him a cassette tape which she used to secretly record the Awaawa Club live so he could make a re-recording of it at his house, although much to his shock, she went there on her first date with another boy, and the sound of the live was overlapped by her and the boy's voices and whispers. Due to that shock, he became absent-minded and accidentally inserted that recorded tape during the afternoon broadcast to record their review meeting, much to Miyamae's own shock, and as she panicked, she yelled “What are you... Idiot” which was recorded on the tape. She got upset as there are hardly any chance of resolving it, so he desperately searched for someone else who recorded the live, but he had to change school due to his parents' job transfer. However luckily, he happened upon a classmate who had the same live recorded on a cassette tape; he made a re-recording and was about to bring it to Miyamae but he died in a fire incident. His spirit lingered however, due to his high determination to bring the tape to Miyamae.
Years later, when members of the Broadcasting Club members found Miyamae's old cassette tape in the innermost part of a shelf and decided to replay it, the spirit of Otobe came causing the broadcasting room to get darker and colder, so they sought Rinne but he runs away upon seeing Sakura as he mistook her for her mother. Rinne and Sakura find his spirit, and after hearing his story, both get surprised upon finding the woman he was looking for, turning out to be Sakura's mother. She believed him to be the son of Otobe, and upon receiving the recorded tape, she got nostalgic and made a joyful reaction, which allowed Otobe to pass on.
- His voice actor also provided the voice of Naraku from Inuyasha.
- The 2 Kanjis of his name "音辺" stand for "Sound" and "Area", which may be connected to his taste for music.
- The tape incident is estimated to have happened 21 years ago, as Sakura's mother was wearing a blue string tie for third year student and is now 39 years old.