Ayame Takeshita[]
Ayame is Isami's foremost rival, with the two of them having fought numerous life and death bouts against each other. Due to this, Isami gained a degree of knowledge of Ayame's skills and ability. Although she is aware of Ayame's outward disdain towards her, Isami grew fond of Ayame because of their repeated fights. When it finally came time for them to decide a final winner during Doll Master's killing game, Isami instead opted for an alliance with Ayame. Deep down though, Isami did consider Ayame a friend. During her dying moments, she choose to make one last move to provide a tactical advantage for Ayame to win.
In the anime, Isami ends up outliving Ayame, who dies first due to Doll Master's machinations. Consequently, Isami is left openly distraught over the loss of her rival.