Giyu Tomioka/Relationships

Tanjiro Kamado
Giyu tries to save Tanjiro from Nezuko Kamado, who had been turned into a Demon, but is shocked to see Tanjiro trying to protect her. After nearly getting taken down by Tanjiro, he senses his potential and sends him to his master, Sakonji Urokodaki, so he can train him to become a Demon Slayer.

While initially hostile towards them, Giyu has come to care a lot about the siblings and willing to violate the Demon Hunters' code of conduct by putting his life on the line in order to protect them.

When Tanjiro was struggling against Rui, Giyu saved him and killed Rui with his Eleventh Style.

Tanjiro is the one who allows Giyu to open up and realize he needs to step up to being the inheritor of the Breath of the Water Style, and not let his past losses and feeling of inadequacy prevent him from realizing this. The two actually have more in common than they think, thinking on similar wavelengths. In some ways, Tanjiro is his closest friend (aside from his late friend Sabito, and, to some extent, fellow Pillar Shinobu Kocho).

He is shown to care a lot for Tanjiro, which is further seen when he becomes greatly angered when Akaza attempts to kill Tanjiro, losing his usual stoic demeanour and jumping in to protect him from the Upper Moon.

Shinobu Kocho
Giyu and Shinobu are both Pillars of the Demon Slayer Corps. They have opposite personalities and initially seem to be at odds with each other. Giyu was shocked when she claimed he just had a grudge on her for saying the others hated him. Despite being at odds with each other, she is the only Pillar who Giyu has interacted with and talked to cordially.

Later on, both he and Shinobu come to care about the Kamado siblings and are visibly upset by the hostile treatment of the other Pillars towards Tanjiro and Nezuko. When Giyu later hears about Shinobu's death, he is visibly shocked and upset by the news. This contrasts to his reaction to death of his other fellow Demon Slayers such as Kyojuro Rengoku, Muichiro Tokito and Genya Shinazugawa, whom he didn't react to so emotionally. This hints that Giyu cares about Shinobu as his friend and not just his colleague.

Sakonji Urokodaki
The former Water Pillar, Giyu's master, and the one who taught him the Breath of Water Style. He holds him on high regard and Sakonji seems to have a lot of trust on his former student too.

Sabito
While Sabito is long dead before the series started, it was revealed that both him and Sabito were best friends as they went through similar situations of losing their family to Demons and bonded well. Later during the Final Selection Exam, Sabito died at the hands of the Hand Demon trying to save his life and others who participated in the exam. Sabito's death caused Giyu to feel so much guilt to the point where he doubted his own abilities as a pillar and rescinds abandoning his position as the Water Pillar.

Tsutako Tomioka
Tsutako is Giyu's older sister. Not much is known about Giyu and Tsutako's relationship, but it was revealed that Giyu and his sister used to have a strong and loving sibling relationship. One night, Tsutako hid the young Giyu and sacrificed herself to protect him from Demons attacking their home. Giyu also cared a lot for his sister that he feels guilty for her death and thought he is better off dead before Sabito snapped at him because of that.

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Гию Томиока Giyu Tomioka