Kanao Tsuyuri/Relationships

Tanjiro Kamado
When Kanao first saw Tanjiro at the Final Selection, they did not have any sort of interaction as she remained aloof and quiet at the end of the ceremony. Later on in the series, when they meet again on Natagumo Mountain, Kanao gets into a physical altercation with Tanjiro as he tries to protect his sister from getting killed and as result gets knocked out cold by Kanao.

Tanjiro is brought to the Butterfly Mansion to recover and sees her in the garden, he immediately recognizes her as one of the survivors from the Final Selection but fails to recognize her as his assailant. Later on when they begin to train, Tanjiro struggles to beat Kanao in all of the tasks due to her advanced abilities but he is able to adapt and beat her. During one of the games, the task is to splash the opponent with a strong smelling tea however instead of dumping it on Kanao, Tanjiro instead places the cup on her head to avoid splashing her, thinking it would be cruel to splash her with something so foul-smelling. When he bids her farewell after recovering, Tanjiro encourages her to be optimistic and for her to open her heart, and flashes her a smile as he bids her farewell. Kanao is seen holding her hands close to her chest and slightly blushing, and falls flat on her face when Kiyo unexpectedly calls out to her from behind.

It is implied in an extra chapter following the end of the Functional Recovery Training Arc that she may have a crush on Tanjiro.

As the story progresses, Kanao starts showing more emotion and decisiveness, especially when Tanjiro is brought back to recover at the Butterfly Mansion following the battles in the Entertainment District. Upon discovering that he had awaken, she drops the flower vase on the floor and tears up while telling him she's glad he had awoken. When the other inhabitants of the Mansion begin to bicker while visiting Tanjiro, she tries to get everyone to quiet down but ultimately ends up yelling at everyone after he falls asleep again.

During the battle against Muzan Kibutsuji, Kanao is left as the only conscious Demon Slayer left and tries to will herself to continue fighting. As Muzan is about to deliver the final blow, Tanjiro momentarily immobilizes Muzan and manages to carry Kanao to safety. Realizing that he has awaken, Kanao sheds tears as she repeatedly calls out his name and he responds to her by apologizing for being late.

After Tanjiro turns into a Demon, Kanao cries when seeing Nezuko trying to calm her brother. Her sympathy for the siblings leads to her once again using Breath of Flower Final Form: Equinoctial Vermilion Eye and create an opening to inject the Demon-to-human cure into Tanjiro, putting her own safety at risk and showing how much she cares for them.

After Tanjiro successfully returns to his human form, she cries of happiness and is visibly relieved to see him safely back as a human, the two exchanging tearful smiles as they lie across from each other.

Kanao and Tanjiro would eventually marry and start a family, having two great-grandchildren by the names of Kanata Kamado and Sumihiko Kamado between them.

Kanae Kocho
Kanae took an interest in Kanao when she saw her being led away as a slave on the bridge. Along with her sister Shinobu, they purchased Kanao from her master and trained her within the Butterfly Mansion. Kanae defended Kanao when Shinobu worried about her indecisiveness and said that if given time, Kanao's heart could blossom. She was the person who gave Kanao the coin she uses to make decisions whenever she is unable to decide things for herself. After Kanae's death, Kanao found herself unable to cry at the funeral, but wears one of Kanae's hairpins as a memento of her. She remembers Kanae's advice in times of trouble, and thinks highly of her. She expresses deep remorse at the fact that she could not cry during Kanae's funeral.

Shinobu Kocho
Shinobu was the one who snatched Kanao away from the slave driver and, along with Kanae, rescued Kanao from her captive lifestyle. Despite being the one to impulsively buy her, she quickly became frustrated when Kanao could not make her own decisions, declaring that she was dangerous to herself and others. Over time however, Shinobu warmed up to her, eventually even making Kanao her Tsuguko. She is very happy when Kanao expresses her wish to train beside her, and the two have a strong sisterly relationship. Before the decisive battle in the Dimensional Infinity Fortress, Shinobu entrusted Kanao with avenging Kanae's death while she used herself as a sacrifice. Even though their revenge goes as planned, Kanao is nonetheless filled with hatred and spite towards Doma. After she and Inosuke kill Doma for good, she fishes through the water to find Shinobu's hairpin as a keepsake of her departed sister. Kanao cries for the first time in the wake of Shinobu's death.

Doma
Much like Shinobu, Kanao holds a strong resentment and hatred towards the Upper Moon for killing Kanae. This grudge grows even deeper after Doma devours Shinobu following their duel, even if it was part of their plan for revenge. Kanao takes immense pleasure and satisfaction at calling Doma out on his inner "emptiness" and non-existent emotions, taunting him by asking him why he was even born and why he continued to bother living if he couldn't feel anything like a normal person would. She eventually kills him with the help of Inosuke and Shinobu's poison.

Inosuke Hashibira
Kanao interacts minimally with Inosuke throughout training. Sometimes, his actions make her see him as a weirdo e.g. - wall-crawling or dislocating all the joints in his arm and relocating them. However, the two end up forming an unlikely duo in the battle against Doma, each fueled by a desire for revenge. They make for an effective team against Doma, aided as well by Shinobu's poison, and are able to decapitate the Second Upper Moon despite neither human combatant even being a Hashira. After the battle, Kanao and Inosuke do not seem to share any dialogue, but quietly grieve their respective and shared losses.

During the course of their battle against Doma, Kanao comes to genuinely emphasize and care for Inosuke. During the Upper Moon's retelling of Kotoha Hashibira's death in which he happily insults and mocks her for her "stupidity," Kanao becomes visibly angry, showing a strong degree of camaraderie and friendship between the two.

Aoi Kanzaki
How close they are is somewhat uncertain, but the two get along and seem to have a somewhat sisterly relationship. Kanao attempts to stop Tengen from taking Aoi with him at a time when it was highly unusual for Kanao to make her own decisions or go against her orders. As seen in the novel, Aoi previously thought of Kanao as difficult to deal with, since she never showed her own emotions. She also felt inferior to Kanao, since Kanao could fight demons and Aoi could not. However, once Kanao starts to open up and make her own decisions, Aoi and her begin to grow closer.

Eventually their friendship grows strong enough that, next to Shinobu, Aoi becomes the closest person to Kanao and one of the people she cares for the most, even considering her something akin to another sister. Kanao in particular comes to enjoy eating every single dish Aoi cooks for her and considers them all her favorites.

Aoi in turn is shown to truly love Kanao and has come to genuinely see her as a sister. So much so that during the time it was Kanao decision to chose a last name for herself, Aoi attempted to discreetly convince her to take her last name to make them as close as genuine sisters.