Tōtsuki Culinary Academy[]
Erina Nakiri[]
Erina has been Hisako's best friend and idol since they were children. Amazed by her prestige and abilities, Hisako has devoted her all into learning the Arato family's legendary medicinal cooking techniques so that she could serve Erina. Since then, Hisako has served as Erina's secretary, choosing jobs for her and is generally wherever Erina is. While Erina always saw Hisako as a companion, Hisako viewed herself more as a servant and aide.
After losing to Hayama in the Autumn Election, Hisako could not bring herself to face Erina, and she took a leave of absence. Hisako eventually returned to Erina's side following the Stagiaire event, having regained her confidence and now willing to walk alongside Erina rather than behind her.
Although their bond of friendship is tight, Hisako was unable to oppose Azami's decision to relieve her of her duties as Erina's secretary. Erina's inability to object to her father also made this impossible to do.
During Regiment de Cuisine when Azami objective declare if his revolution, Erina will be suffering misery in the wasteland all alone, but Hisako defend this and express her belief that everyone gotten as far as they did because everyone head toward their own goals and that others who continue to move forward, which allows them to take another step forward. Azami, enraged at Hisako for openly opposing the Director of the Academy, is stating that she nothing more lowly servant for the Nakiri family, however, Hisako disagrees, declaring that she is Erina's friend which left Erina touch by her declaration.
After the Regiment de Cuisine, Hisako returns to her duty as Erina's Secretary and continues to aid her in her new role as the Director of Totsuki the two of them has gone much more closer since then. When Erina asked about Hisako what she had said at the Regiment de Cuisine Hisako frantically tell her forget about what she just said believing that it was audacious of her for saying that they're friends. However, Erina's insist that she wasn't audacious and request her call her Erinacchi like the others, but Hisako exclaims that she could never call her that then Erina suggest to call her Erina-chan because they're friends when Hisako complied both of them became extremely embarrassed by it and choose to with Erina-sama, but they become much closer then before.
Sōma Yukihira[]
Erina's former arch rival who hails from the humble Restaurant Yukihira. Upon her encounter with Sōma, Hisako deemed the boy was "disrespectful" to Erina when he nonchalantly chatted with Erina, despite their different positions. Because Erina deemed Sōma as a "threat" in her life, Hisako made an effort into trying to send Sōma packing away from Tōtsuki for Erina's sake.
Like her fellow students, Hisako belittled Sōma, despite his ongoing success until the Autumn Election Quarterfinals where she was defeated by Akira in a hamburger battle. Unbeknownst to Hisako, however, Sōma was among the Autumn Election Finalist and ranked in Second Place (tied with Ryō). Even when she became Sōma's unexpected partner during the Stagiaire event for the Restaurant Mitamura, Hisako remained skeptical upon Sōma until she witnessed his uncanny performance by handling even the overcrowding customers in the restaurant. Despite Hisako's initial hostile behavior to him, Sōma maintained a friendly attitude towards her. The two were partnered Stagiaire event, Sōma helped her regain her confidence.
Because of Sōma's assistance in getting her to try and stand beside Erina as an equal rather than in her shadow, Hisako now displays a much friendlier attitude towards Sōma and enjoys his company, something that even Erina finds hard to believe as she was surprised the two had become good friends.
Hisako tells Erina that she believed Sōma would be the one to stop Azami. During the Regiment de Cuisine, she treats him with utmost respect after Sōma defeated Somei Saito, the 4th Seat of the Elite Ten.
Nao Sadatsuka[]
In their middle school years, Hisako was challenged to a Shokugeki by Nao for the position of Erina's secretary. Hisako won the duel and Nao was forced to stay a minimum of 50 feet away from Erina at all times. Since then, Nao sent 30 letters daily to Erina, but Hisako intercepted them and disposed of them immediately. The two finally had an opportunity to face each other during the 43rd Annual Tōtsuki Autumn Election during the preliminary round. In the end, Hisako's dish was superior and even Nao was temporarily "exorcised" as a result. Unfortunately for Hisako, Nao has developed a similar stalker crush on her as she did for Erina even calling her "Hisako Onee-sama".
This new attention and change in demeanor causes both confusion and uneasiness for Hisako.
Akira Hayama[]
Hisako's first opponent for the Autumn Election Main Tournament was Akira. Both he and Hisako shared their professionalism in food forte, especially in spices and herbs. Because Akira was planning to replace Erina as the Elite Ten Council member, Hisako took a dislike to him and belittled Akira for thinking he could defeat Erina. Unfortunately, not only did she lose to Akira in a hamburger match, but was also criticized by Akira for her lack of ambition and limited vision of the culinary world, as well for her loyalty towards Erina, which he deemed her as Erina's "No. 2".
Her defeat at his hands caused Hisako to feel extremely upset and ashamed of herself, and she was unable to face Erina afterwards.
Others[]
Mamoru Mitamura[]
The owner of the Western Cuisine Mitamura and also Hisako's supervisor during the Stagiaire event.