My Hero Academia is a "magical high school" story with a huge cast of colorful characters, most of them adolescents training at the elite U.A. school to become pro heroes someday. The star is Izuku Midoriya, and he was put right into class 1-A, with Tenya Iida as the class rep. Meanwhile, class 1-B has Itsuka Kendo as the class rep, and she is Tenya's equal in many ways.
Itsuka may not be the strongest trainee in her year, but she is responsible, cool under fire, and has a personality that fits the "big sister" role well. She also has a melee Quirk known as Giant Fist. Are there any other anime characters out there who fit those traits?
10 Maki Oze (Fire Force)
Maki Oze is a fire soldier, and her ignition ability allows her to control flames to a highly advanced degree, often forming two fireballs with cartoony monster faces on them. She also recently learned to create a devastating flame tornado that can defeat powerful Infernals.
Like Itsuka, Maki is tough but kind, and she even had a background as a soldier before joining the fire soldier platoons instead. She may not be the commander, but she's reliable and has a good time training Shinra Kusakabe and Arthur.
9 Yoruichi Shihoin (Bleach)
Yoruichi Shihoin is an ex-Soul Reaper, but she's forgotten none of her skills from her days as squad 2's Captain. Unlike many other Soul Reapers, Yoruichi relies on martial arts in combat rather than her zanpakuto or advanced kido spells.
Yoruichi is a great mentor and friend for Ichigo Kurosaki and his friends, just the way Itsuka is for her classmates. And like Itsuka, Yoruichi has a preference for melee combat, and is much stronger than she looks (especially when she uses the Shunko technique).
8 Asuma Sarutobi (Naruto)
Asuma was a man in his early-30s when he died at the hands of the Akatsuki, but his personality was similar to Itsuka's, and if he met her, he'd be very impressed. Asuma was a leadership figure, almost a father figure, to squad 10.
Being tough but kind is Asuma's way, and he saw the potential in his three genin subordinates and worked hard to help them cultivate that potential. In combat, he can use bladed brass knuckles with chakra on them, as well as flaming ash techniques.
7 Erza Scarlet (Fairy Tail)
In the land of Fiore, everyone knows the name Erza Scarlet. This red-head is a master swordsman, the best of her kind, and she can use magic to equip all kinds of suits of armor in the middle of combat. Erza's endurance is legendary.
On top of that, Erza has a tough, mature personality that makes her like a big sister, much like Mirajane Strauss (who actually is a big sister). Erza can keep her rowdy teammates like Gray Fullbuster and Natsu Dragneel in check without any trouble.
6 Lisa Lisa (JoJo's Bizarre Adventure)
In the Battle Tendency story arc, hero Joseph Joestar urgently needed a teacher to help him unlock the potential of hamon, and he found that teacher in Lisa Lisa (who is in fact his mother). And like any good shonen teacher, Lisa Lisa was demanding and thorough.
But she also believed in Joseph, her son, and was confident that he could survive that hellish training and become a great warrior. She was right, and Lisa Lisa was also ready to fight right alongside Joseph and Caesar to vanquish the vampires.
5 Darkness (Konosuba)
The crusader known as Darkness has a few differences with Itsuka, such as her noble upbringing in the Dustiness family and her poor aim in combat. In many other ways, though, Darkness is rather like Itsuka, being a reliable and fearless fighter at close range.
She is a good friend, too, and makes sure that everyone is on their best behavior. Darkness will give anything for her friends, even the sleazy Kazuma or the bratty Megumin, and she cherishes them like her new family. Though she could stand to stop goofing off herself— she enjoys getting beaten up in combat.
4 Shizue (That Time I Got Reincarnated As A Slime)
Shizue was an isekai hero before Rimuru Tempest showed up on the scene, and Shizue was a very kind young woman in a world engulfed with strife and bloodshed. Shizue trained and protected a squad of children who had magical potential, and she passed that mission on to Rimuru later on.
All those kids saw Shizue as a big sister, or even as a foster mother, and Shizue was a fearless and powerful warrior who could take on the strongest foes and vanquish them to keep her young charges safe. Just the kind of protective figure Itsuka Kendo can be.
3 Naofumi Iwatani (The Rising Of The Shield Hero)
Naofumi Iwatani, the shield hero, had some pretty dark anti-hero moments, but otherwise, he's almost like Itsuka Kendo's long-lost brother. He, like Shizue, found himself in a brand-new fantasy world, and he made sure to lo0k after the people who are important to him.
Fans view Naofumi as the isekai genre's best dad, since he has such a paternal role with Raphtalia and Filo during their action-packed adventures. Naofumi is strict and demanding, but also highly protective and caring, patiently helping Raphtalia and Filo realize their potential.
2 Mikasa Ackerman (Attack On Titan)
Mikasa is often considered Best Girl of her series, and it's easy to see why. Mikasa Ackerman ranks highly among the Scouts, and since her girlhood, she has been highly protective of her friend Eren Yeager. And in fact, Eren soon learned to rely on her and her reputation among the town's children for protection.
Mikasa is calm and mature during missions, efficiently dispatching any Titan that gets in her way. But if Eren is in trouble, Mikasa will unleash her wrath, since she would sooner perish than see any harm befall her dearest friend. Itsuka can relate to that.
1 Katara (Avatar: The Last Airbender)
Katara of the Southern Water Tribe is the younger of two siblings, but she often acts as the older one. Her father Hakoda requested that Sokka protect his younger sister, and Katara has returned the favor more than a few times. And it was she who first trained Aang how to bend water, until master Pakku took over.
Katara is responsible, practical and emotionally connected to everyone around her, and at first, Toph found this tiring. Before long, though, Toph came to realize that Katara's motherly ways are actually a blessing, and Toph started to really look up to her.