上代 由香里

Yukari is the vice-homeroom teacher to Yuuto's class and is an old friend of Ruko. She is referred in the story by Yuuto as the "sexual harassment teacher". She is constantly smiling, though she enjoys teasing trouble makers. She likes spending a lot of time over at the Ayase house, and is unmarried though wants a boyfriend. At school, she is in charge of teaching music. She is twenty-three years old, though refers to herself as "eternally seventeen". There is a possibility that she is the rumored teacher that graduated from this same school and famous in the music world as the Performer of the Sunset.