Demon Slayer is a smash-hit fantasy shonen series featuring a relatively small but beloved cast of characters, mainly sword-carrying demon slayers who risk their lives to shield humanity from the monsters in the dark. That includes the nine elite Hashira, and some of the Hashira have direct subordinates, such as Tengen Uzui, the sound Hashira.
Tengen prides himself on being flashy and dazzling, and he has a bit of a temper, too. But deep down, he is also a caring and compassionate fellow who cherishes the three kunoichi who follow him, his three wives. Tengen trusts each of these female warriors with his life. However, if he wasn't fortunate enough to have them by his side, he would have to recruit a warrior-wife from another anime series, and only a reliable, brave, and noble character can fit the bill.
9 Yoruichi Shihoin Fears No Demon (Bleach)
Ideally, Tengen's warrior-wife will be someone he can get along with on a personal level, a woman whom he cherishes and respects. A good start is the deadly assassin Soul Reaper Yoruichi Shihoin, who can give Tengen a run for his money.
Yoruichi is easily on par with the Hashira, but she would still volunteer to aid him on a mission, and she can do things Uzui's current three wives can only dream of. And it helps that Yoruichi's flamboyant, energetic personality matches Tengen's own.
8 Kurenai Yuhi Is Kindhearted & Smart (Naruto)
Kurenai Yuhi is also a ninja, just like Yoruichi and Tengen's three wives, which makes her an obvious candidate. Like Yoruichi, she has skills that Tengen's three wives can't even imagine, since she has the power of ninjutsu on her side. Few, if any, Demon Slayer characters can create convincing illusions like that.
Yoruichi can fool any opponent with her plant-themes genjutsu, and this buys time for her teammates to finish the job. Meanwhile, Kurenai has a mature and warm air about her that would make her intently appealing to Tengen.
7 Ryukyu Can Morph Into A Dragon (My Hero Academia)
Ideally, Tengen would recruit the melee hero Mirko as his wife, but Mirko doesn't like working in teams, so Tengen will try Ryukyu instead. Ryukyu is almost as powerful as Mirko and has a much stronger sense of teamwork, and she has a mature and humble personality to match. So far, so good.
Ryukyu is an experienced and tough pro hero who would see demons as peculiar villains to be slain, and she wouldn't even fear the Moons in combat. Her Quirk, meanwhile, morphs Ryukyu into a scaly dragon, perfect for shielding innocents from harm or pinning down a powerful demon.
6 Maki Oze Knows Her Duty (Fire Force)
The fire soldier Maki Oze is a great pick for any anime superhero team, since she has formidable discipline and courage from her time in the Tokyo Empire military, not to mention her remarkable second-generation ignition ability. She styles herself as a fire witch, and she can dispatch Infernals with ease.
Maki's experience as a monster hunter makes her a natural fit for Tengen's team, and Tengen would also like Maki's confident, colorful personality and strong will. The two of them would quickly become friends, to say the very least.
5 Shion Has A Flashy Personality (That Time I Got Reincarnated As A Slime)
Shion is an ogre who carries a huge sword into battle, and she has a confident and fun-loving personality to match. Tengen would approve of Shion as a flashy and powerful fighter, and he would convince Rimuru to let her join his team for a few missions.
Shion is a cheerful and warm-hearted warrior who would easily get along with Tengen Uzui and support him however she could during a mission, either with her fists or her sword. It wouldn't take Tengen long to see why Shion is one of Rimuru's most trusted and valued subordinates. She's definitely something special.
4 Asuna Yuuki Has A Kind Heart (Sword Art Online)
After years of playing MMORPGs, Asuna Yuuki grew up into a powerful and skilled gamer and swordswoman in a variety of virtual worlds. She has always been a brave and noble young lady, and now, after countless adventures with Kirito, she's ready for a new mission.
By the events of the Unital Ring arc, Asuna is a powerful warrior who fears no enemy, and Kirito trusts her with his life, so Tengen would do the same. He and Asuna would get along great if they fought on the same team, and if Kirito weren't around, they just might grow even closer.
3 Jolyne Cujoh Is Pretty Flashy, Too (JoJo's Bizarre Adventure)
Jolyne Cujoh is the sixth Joestar hero and the protagonist of the Stone Ocean story arc. Jolyne was falsely accused of a horrible crime, and found herself in the Green Dolphin Street prison in Florida. In that ocean of stone and metal bars, Jolyne gained the power of Stone Free, her Stand, and put it to good use.
Given the chance, Jolyne would gladly team up with Tengen as his newest ally in exchange for her freedom. Like Tengen, Jolyne has a flashy and strong personality, and she won't let anyone cross her. She and Tengen will get along great.
2 Mirajane Strauss Believe In Teamwork (Fairy Tail)
Mirajane Strauss is one of the Fairy Tail guild's strongest wizards, if not the very strongest, but she's not liable to boast about it. Mirajane greatly prefers peace and even volunteers as a barmaid, but if anyone threatens her guild, she will let loose with her formidable Take Over magic, turning her into a demon.
Even if Tengen is trained to slay demons, he would accept Mirajane to the team, and he'd be enchanted by her warm, caring, and responsible attitude as a mighty wizard. She could even take on the Upper Moons with Tengen by her side, and no doubt they'd grow much closer after a few battles together against Muzan's hordes.
1 Diane Is A Flashy Giant (The Seven Deadly Sins)
Diane is a giant from the land of Megadozer, the home of the warlike giant race. These titanic humanoids love battle and bloodshed, but Diane is far nobler than that. She favors peace over war, and she only fights to defend her friends and protect the innocent, not for glory.
Tengen would approve, and he would also be dazzled by Diane's energetic and cheerful personality. She would make a fine addition to the team, but it would help if she used her human form in between battles, or else the demons will see her coming from a mile away.