Kyōko Ono is a homeroom teacher at Kōryō High School.
Ono has a rather carefree, kind and softhearted personality for a teacher, commented on many times by superintendent Yasunaga. This even comes to the point where she relies on Boris Ivanov to uphold order as her class monitor when the YOMI member "transfers" to the school.
Out of all of the YOMI transfer students, she held a deep respect for Boris, particularly due to Boris doing anything she asked without hesitation and always did good deeds at the school that left a great impression on her, stating she would miss him a lot for his actions. When Boris had to go home, it left Ono crying tears of sadness (for him leaving) but also of joy (for his last good act as a student of the school). She was also oblivious of his fight with Kenichi, believing they were just having fun as friends.
Ono is a young woman of average height with short dark brown hair, glasses, and is usually seen in a casual teaching outfit or a jogging suit while on the camping trip or heavy clothes on the ski trip.
She can speak in Russian as her second Foreign language.
She can also, unknowingly, sneak up on highly trained martial artists to the point they were unaware she was next to them until she spoke. This has lead to them to believe she is secretly a Master Class.
- Her name is likely based off of Yoko Ono, Japanese singer, artist, and filmmaker, among other things.