Sakuya's calssmate. Always acts high and mighty; she proclaims herself as Sakuya's rival in conquering their Kanade Sakurai's heart. SpoilerIt is later revealed that she is very poor since the death of her father. While she seemingly competes Sakuya for winning Kanade's heart, it the end it turns out that it is in fact Sakuya that Isako has feelings for.
