Tengen realized his father's trick only after he had killed two of his brothers. By the age of 15, seven of his siblings had already died leaving only him and his younger brother who is two years younger.
Three of his siblings died due to their father's overzealous training. The remaining six was then placed on death battles against each other while being masked.
During his conversation with Gyutaro in the manga, Tengen admitted that his father made the Uzui children fight to the death while blindfolded and unaware they were fighting each other, resulting in Tengen being responsible for the deaths of two of his own siblings.
This has been on my mind for a very long time, but it recently sparked even further interest with Uzui's debut in the anime adaptation. Out of all of his siblings, only his younger brother survived.
The unnamed ninja of the Uzui family is the father of Tengen Uzui and eight other unnamed siblings, and is a sociopathic and abusive ninja clan leader who sees his clan's survival over his family.
Tengen Uzui loves all of his wives equally, but he was actually set to have a different wife. He was supposed to marry Suma's younger sister, but Suma had other plans.
Makio is actually a distant cousin of Tengen's.
Shinobu Kocho is a capable Demon Slayer whose worthy of being the Insect Hashira. That being said, she's arguably the weakest Hashira when it comes to pure strength.
The core components of a Demon Slayer's strength comes down to one's Breathing Style, battle IQ, and physical strength. These are even more important for those at the Hashira level, who will likely combat Kizuki rank demons regularly. In these three regards, Tengen Uzui is far from the weakest Hashira.
1 Gyomei Himejima - The Stone Hashira
The oldest of the bunch, the Stone Hashira, Gyomei Himejima is 27 years old.
No one killed Sanemi Shinazugawa. Sanemi almost died when he tackled his sister Genya from a window in order to protect her from a demon attack, but was saved by his friend Masachika who healed his wounds.
If he was to survive, these extremely bad wounds will force him to retire and he will never fight again. // Tengen would still lose his eye and arm. Tanjiro was completely helpless against Gyutaro without Tengen, which was why he had to 1v1 him and got his hand sliced.
Sensing their despair, Doma offered a chance to him and turned both Gyutaro and Daki into demons.
Entertainment District Arc
At the beginning of the arc, Tengen enters Butterfly Mansion and attempts to kidnap Naho and Aoi to assist him on his mission. However he is forced to change tactics when the three boys —Tanjiro, Zenitsu and Inosuke Hashibira— rescue the girls, and force him to take them along on his mission.
According to the second fanbook, Makio is actually a distant cousin of Tengen's.
After becoming a Hashira, Tengen knew that his life would come to an end one day, so he started living a flashy life and became the most flamboyant individual in the series. His flashiness is a reminder that one day he is going to die, and that is why he started living life like there was no tomorrow.
But there is one who is the friendliest of them all, and that is Kiyogiro Rangoku, the Flame Hashira. Among the pillars, there is not a single negative thing revolving Rangoku. Such an honest guy, and his character influences others positively. In Demon Slayer, Liu and Rangoku are not shown to have any interactions.
7 The Love Hashira - Mitsuri Kanroji
Kanroji first joined the Demon Slayer Corps not to improve on her own fighting abilities, but to find a suitable husband, as she believes her husband must be stronger than she is.
Gyomei Himejima
Gyomei Himejima, the Stone Hashira, is the strongest Hashira in the Demon Slayer corps in terms of strength and swordsmanship. He is the only person who uses spiked flails and an axe instead of standard swords to kill demons.
Muichiro Tokito: The Mist Hashira with a Mysterious Aura
Among the Hashira, Gyomei Himejima stands out as the Stone Hashira, with unmatched raw physical strength.
The Insect Pillar of Demon Slayer Corps, Shinobu is undeniably the smartest individual. She might not be physically stronger than others, but her intelligence is what kept her going. Shinobu is proficient in medical knowledge and can also create poisons out of wisteria flowers that are lethal to demons.
Canon. Uzui and Rengoku are the fellow Hashira of the demon slayer corps. being the Sound Hashira and Flame Hashira uzuren is the besr ship. In Rengoku gaiden, when uzui first met Rengoku he stated that he's flamboyant and likes this guy.
Makio is actually a distant cousin of Tengen Uzui's.
At some point of her life, Suma married Tengen Uzui, along with Makio and Hinatsuru, although she volunteered to be his wife while the other two were arranged marriages. After she left the clan, her family journeyed to see Kagaya Ubuyashiki in order to fight as a part of the Demon Slayer Corps.