In the 1960s she was the President of the Classics Club when she was a second-year student at Kamiyama High School. Now she works as librarian at the same school.
Youko's husband is briefly shown in a semi-flashback on her age.
Youko's daughter is briefly shown during the aforementioned flashback.
- The name Youko means "Nourishment" (養) (you) and "child" (子) (ko).
- Youko's surname Itoigawa means "yarn" (糸) (ito), "fish" (魚) (i) and "river, stream" (川) (kawa/gawa).
- Her maiden name Kooriyama means "county" (郡) (kori) and "mountain, hill" (山) (yama).
|Classic Literature Club series and Hyouka featured characters|