Appearance: Kyojuro was a young man of tall stature and lean-muscular build, with fair skin. He had long, somewhat messy and bright yellow hair that flared out around his face, with red streaks akin to flames along with two shoulder-length bangs, two chin-length bangs on the side of his head, and wore a messily ponytail behind his head. He had black forked eyebrows and golden eyes that turns to red around the irises with white pupils. He was known to be charismatic and had an air of great optimism, having an enthusiastic smile plastered on his face nearly all the time. Kyojuro wore the standard Demon Slayer Corps uniform, which is black in the manga and tinted a deep brown in the anime. It consisted of a brown button-up jacket with a stand-up collar and long sleeves, featuring gold buttons and a shirt pocket on the left breast, with the kanji for Destroy (滅めつ, Metsu?) engraved on the back of the uniform. Beneath the jacket, he wore a white long-sleeved collared undershirt. His uniform was fastened with a white belt at the waist and included traditional tattsuke-hakama pants of matching color. Over this, Kyojuro wore a striking haori draped on his shoulders like a cape, with a white-to-yellow gradient pattern and red flame-like ridges at the end. This haori originally belonged to his father, Shinjuro Rengoku, and was more than likely worn by him when he served as the Flame Hashira before Kyojuro inherited the role. For legwear, he wore a pair of red kyahan decorated with yellow flame motifs rising from the bottom up, brown tabi socks, and a pair of white zōri sandals with red straps. Energetic, kind, clingy, loving, loud, passionate.

Giyu is a fairly tall young man of a lean muscular stature and pale complexion, consistently seen wearing a stoic expression. He has 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 a choppy fringe. His eyes are sharp and moderately large; his irises are lapis blue that fades into a lighter shader at the lower part, surrounded navy blue pupils. His irises are sometimes completely opaque and empty. His eyes are framed by thin eyebrows. Giyu wears the standard Demon Slayer Corps uniform, colored black in the manga and tinted charcoal blue in the anime. It consists of a button-up jacket with a stand-up collar and long sleeves. Additionally, it features gold buttons and a shirt pocket on the left breast, with the kanji for Destroy (滅めつ, Metsu?) engraved on the back of the uniform. Beneath the jacket, he wears a white long-sleeved collared undershirt. The uniform is fastened at the waist with a white belt and includes a pair of matching tattsuke-hakama pants, wrapped at the calves with buttoned white kyahan. On his feet, he wears tabi socks that match the tone of his uniform, along with white zōri sandals with navy blue straps. Over this, Giyu wears a distinctive haori that is split down the middle into two contrasting halves - the right half being a carmine color, the left half decorated in a traditional geometrically patterned rhombi consisting of green, dark green, orange, and yellow. These haori halves are sentimental mementos, with the red side formerly belonging to his late older sister, Tsutako Tomioka, and the patterned side to his deceased friend and fellow apprentice, Sabito. Loving, clingy, gentle.