|Ibuki Kouko伊吹 公子 AB|
|Measurements||Height: 161cm, Weight: 49kg|
|Hair||, Brown, Short|
|Role||, Full Sister, Older Sister, Teacher|
|Visual novels||Side character - Clannad|
|Voiced by||Minaguchi Yuuko|
Kouko is Fuko's older sister. She used to be an art teacher at Hikarizaka high school, and she treats everyone kindly. Kouko is one of the familiar faces in the Furukawa Bakery, and Nagisa admires her very much, being her former art teacher.