Minata was the former master of Sakuya whom she cared deeply for and possibly loved. Not much is known about their past events together except what is seen when Sakuya's memories are shared with Kotarou. Minata snuck away from her residence and seemingly encountered familiars; Sakuya appears and 'rewrites' himself in order to protect her, afterwhich he scolds her from running away. Sometime later he announces that he has spotted the Key and is going to rewrite himself in order to engage it; Minata warns him that his body is at its limit but he ignores her and leaves while promising to return to her. Sakuya fails to stop the Key's salvation; Minata disappears while thanking Sakuya for all that he's done for her.
- Since Sakuya is seen wearing 'samurai' clothing when he became Chihaya's familiar it is possible that she and Sakuya lived in the Fuedal Era.
- Since Sakuya has a phobia of cats they likely kept cats as pets.