Tengen Uzui

Faster, faster! Is this how you want to kill demons?! You can't even run one lap!
He followed the young hunters who were training.

However, Tengen does possess a caring side that is masked under his flamboyant façade, one he only shows to those that are extremely close to him, most notably his three wives, Makio, Suma, and Hinatsuru, who Tengen is shown to truly care for, praising and encouraging Makio and Suma after their undercover mission
and assuring Hinatsuru that she has completed her mission and telling her to get out of harm's way.
Furthermore, Tengen also declares that they must value their lives above all others as they are precious to him. This is especially shown when Gyutaro gags Hinatsuru with his hand, Tengen panics and furiously yells at the demon to leave his wife alone. After the events in Yoshiwara, Tengen also becomes more friendly towards Tanjiro, Zenitsu, and Inosuke.
Although he can be very boastful and expressive, Tengen also shows a side of modesty and humility. He openly denied Gyutaro's statement that he was blessed with any talent, comparing himself to the other Hashira and especially Kyojuro Rengoku. This implicates a sort of inferiority complex, further proven by the fact that he told himself that he could never become someone as great as Kyojuro. Tengen is also shown to harbor regret over the fact that he has let so many lives slip through his fingers over the years. Kagaya Ubuyashiki praised Tengen for the hard path he chose and for facing forward and fought to protect human lives despite carrying all of his conflicts and contradictions he hides behind his loud and confident façade, which caused Tengen to deeply respect Kagaya from that moment on.
Despite being a shinobi that has traditionally valued completing the mission over all else, Tengen has rejected that ideology after seeing its effect on his family.
He believes that his subordinates, whether they be his wives or the Demon Slayers under his command, should value their lives, and the lives of innocents, over their missions or his own.