Giyuu tomioka

Giyu is a fairly tall young man of a lean muscular stature and pale complexion, who is almost always seen wearing a stoic expression. He has choppy raven-black hair of uneven lengths, with jaw length side-bangs, a low messy ponytail at the base of his neck, and bangs falling over his eyes in an choppy fringe. His eyes are sharp and moderately large, their irises a navy blue that fades to a sky blue and their pupils a bluish-black, sometimes having his irises completely opaque and empty, just in dark blue color, and are framed by thin eyebrows.

Giyu wears a dark blue-tinted version of the standard Demon Slayer uniform, consisting on a button-up jacket with stand collar and long sleeves, a white belt, and a tattsutake hakama pants wrapped by white kyahan, having a pair of white zōri with dark blue straps and tabi socks underneath being the same color as his uniform. Over this, Giyu wears a haori that's split down the middle into two different patterns: the right one a solid dark red, and the left one geometrically patterned with rhombi of green, dark green, orange, and yellow. These haori were later noted to have belonged to his late older sister, Tsutako Tomioka, and his deceased friend Sabito.[6]

During his battle with Muzan Kibutsuji, he loses his right arm.[7] After the fight, Giyu cuts his hair down to neck length, and he is seen wearing a button-up collared shirt under a kimono, and umanori hakama pants.[8]

While Giyu was training under Sakonji Urokodaki, he wore a red haori which would later make up his current one as well as black tucked-in tattsuke-hakama pants and his current white leg-wrapped kyahan and pair of white zōri with dark blue straps. In addition, he also wears the warding masks that are signature to Sakonji's pupils. For Giyu, it is a white fox mask with light blue eyes

Giyu is a man of strong equanimity, therefore, always wearing a calm and stern expression on his face. However, he has a stoic personality and a very strong sense of justice, and responsability. He have no tolerance towards those who don't know their own limitations and throw away their lives.[9] Despite letting Nezuko Kamado live due to Tanjiro Kamado's persistence, he shows zero hesitation when killing other demons and has no respect or mercy towards them like most Demon Slayers.[10] Even so, Giyu violated the Demon Slayer Corps' code of conduct without hesitation to protect Nezuko during Shinobu's attempt to kill her. This implies that he doesn't completely despise demons as some other Hashira do, and is willing to make an exception for a demon by letting them live if they don't kill and eat humans. This shows that he is more pragmatic and impartial in dealing with demons rather letting his hatred cloud his judgement.

Giyu shows to have concern with what others think of him, by being shocked when Shinobu Kocho claims he is hated by others.[11] Besides that however, he doesn't seem to care about Shinobu's other teasings, even ignoring her. Despite that, they are in fact friends with a good amount of history together. He is a man of very few words and isn't very good interacting with others, so he usually keeps himself at a distance.[12] He even goes out of his way to tell Akaza that he hates talking, and wants to keep his name to himself, as he thinks names are not meant to be shared, especially to demons

Beneath his seemingly unemotional and aloof attitude, Giyu suffers from an inferiority complex which he developed since his participation in Final Selection. This self-doubt in himself reached the point where he contemplates abandoning his position as the Water Hashira until Tanjiro helps him realize that instead of acting on his survivor's guilt, he should cherish his life and live on for the people who sacrificed their lives for him.[13] This feeling of survivor's guilt strikes again when he believes Tanjiro has died after the fight against Muzan. Giyu, while he sheds tears, admits how he is always the one who is saved.

Despite his stoic nature, Giyu is shown to be protective and caring towards those he is close to and considers his friends. This is first shown when he puts his life on the line for Tanjiro and Nezuko by vowing to commit seppuku if the latter were ever to eat a human.[14] Giyu has been shown to lose his composure and usual stoic demeanor when those he cares about are in danger, as seen when he is greatly angered by Akaza's attempt to kill Tanjiro and visibly shocked when he hears the news of Shinobu's death.[15] This is further shown in the fact that he still wears half of Sabito, his late best friend's, and his older sister's haori as a memento of them. However, Giyu appears to be particular in who he shows emotions for, as he doesn't appear to react at all when informed of the passing of Genya Shinazugawa and Muichiro Tokito.

Despite this, Giyu will not let his personal relationships get in the way of his duty. When Tanjiro begins his assault as a demon, Giyu is the first to announce that they need to take him down, despite his brotherly-type relationship with Tanjiro. Following the death of Muzan Kibutsuji and the eradication of demons for good, it is clear that Giyu has been able to embrace his happier side, shown by his smiles towards the Kamado siblings and even Sanemi, which shows how much their combative relationship has slowly developed into one of mutual respect.

As a Hashira of the Demon Slayer Corps, Giyu is a very powerful and skilled combatant.[16] From the beginning, Giyu showed how much he outclassed Tanjiro and his friends, being able to effortlessly capture Nezuko from him and later knocked both of them unconscious in a single blow. Later, he was able to easily defeat Father in his transformed state[17] and Rui, Lower Rank Five,[18] something Tanjiro and Inosuke respectively failed to accomplish. He also fought equally against fellow Hashira Sanemi Shinazugawa in a sparring match. Giyu was also shown easily beating dozens of demons equal to that of the Lower Ranks of the Twelve Kizuki. On top of his incredible skills as a Demon Slayer, Giyu is also a very capable teammate, able to grasp their intentions and work in tandem with it.

Master Swordsman: Being a Hashira of the Demon Slayer Corps, Giyu is one of the most powerful and skilled swordsman in the entire organization.[26] Upper Rank Three, Akaza, who has fought countless swordsman in the past, was impressed with Giyu's skill, stating that he possesses finely developed swordsmanship.[27]

Breathing Style Water Breathing (水みずの呼こ吸きゅう, Mizu no kokyū?): A Breathing Style taught to him by the Water Hashira before him, Sakonji Urokodaki. As the Water Hashira, Giyu is his generation's most skilled Water Breathing user. Giyu has completely mastered this swordsmanship style, to the point that he created an entirely new technique within the Breathing Style and impressed Akaza who had fought Water Hashira in the past.