In anime, the main character is, of course, the center of attention and the one who drives the plot forward (and is also protected by it). However, in many cases, there are side characters that steal a lot of that attention away from the main character, and are equally beloved by fans.
There are thousands of anime's, but only ten spots on this list, so unfortunately not every adored side character could make the cut. And just as a rule, deuteragonist will not be on this list, that includes all-time characters like Vegeta (Dragon Ball) and Sasuke (Naruto). Additionally, with apologies to One Piece fans, Zoro, Sanji, and the rest of the Straw Hats won't be here either, as they are as much as main characters as Luffy, and honestly, it wouldn't be fair to the rest of this list.
Satoru Gojo - 'Jujutsu Kaisen'
The newest character on this list, Jujutsu Kaisen took the anime world by storm when its first season debuted in 2018. Satarou Gojo, the sensei to Yuji Itadori, Megumi Fushiguro and Nobara Kugisaki, is the strongest character in the verse.
His piercing blue eyes and absolutely overpowered techniques, along with his funny and goofy personality, have made him one of the most lovable characters in anime in an extremely quick manner. Not to mention, he absolutely stomps out whomever he fights.
Shoto Todoroki - 'My Hero Academia'
The son of the number two Hero (number one after All-Might retires), Endeavor, Todoroki has a quite, aloof, and cold (pun intended) personality. He is also a student in Class 1-A, along with series protagonist Izuku Midoriya and Katsuki Bakugo.
Gifted with the duel Quirk, Half-Cold Half-Hot, he is able to control fire (his Father's Quirk) with the left side of his body and ice with the right side. Initially, Todoroki only uses his ice side due to his resentment and disdain for his father.
Kenpachi Zaraki - 'Bleach'
Kenpachi is the Captain of the 11th division in the Gotei 13 and one of the strongest characters in the series. Kenpachi relishes combat, and he actually suppresses his full strength so battles last longer.
His Bankai mimics that desire for combat, transforming himself into a full on berserker demon with unreal strength and an even stronger lust for battle. Kenpachi's design and overall love of combat would make you think he is a villain if you didn't know anything else about the show.
Roy Mustang - 'Fullmetal Alchemist: Brotherhood'
Colonel Mustang is the superior officer and mentor to series protagonist Edward Elrich. Known as the flame-alchemist, Mustang can create powerful flames by snapping his fingers using alchemy along with his specially made gloves.
Though he gives off a very cold and cocky personality, but he is far from it. He cares a great deal about his subordinates and anyone who is willing to fight alongside him, and especially to those who cannot protect themselves.
Future Trunks - 'Dragon Ball Z'
Future Trunks makes a huge splash when he is introduced in Dragon Ball Z. After a rebuilt Frieza and King Cold arrive back on Earth for revenge against Goku, Trunks appears and completely annihilates them. After turning Super Saiyan, just the second character to do so in the series, Trunks dices Frieza into a million pieces and then embarrasses King Cold.
Although Trunks is the son of Vegeta and Bulma, Future Trunks hails from a future that was decimated by Androids 17 and 18, which is why he comes back to warn Goku and the others. He also aids them in their battle with Cell.
Gol D. Roger - 'One Piece'
The King of the Pirates. Although not a main character, he is the reason for the events of One Piece unfolding and the drive behind Monkey D. Luffy's desire to be Pirate King. Roger conquered the Grand Line before the events of the series and his impact is still heavily felt throughout the world.
Possessing a high level of all three kind of Haki, Roger is undoubtedly one of, if not the single strongest character in the entire series. He is also the biological father of Luffy's brother, Portgas "Gol" D. Ace. Luffy's iconic straw hat can be traced back to him as well, since he gave it to Shanks, and Shanks gave it to Luffy at the beginning of the story.
Levi Ackerman - 'Attack on Titan'
Levi stands at just 5'2" but is the strongest character in Attack on Titan, and that includes Titan shifters. He is a total neat freak, probably stemming from the fact he grew up in the underground before joining the scouts. But he also, like many other characters on this list, gives a cold and emotionless persona, when in reality he cares deeply for his comrades.
Mikasa, also being an Ackerman, is the only one who could rival Levi's speed and strength. He is literally so overpowered, creator Hajime Isayama had to sideline him for a good portion of the early part of the series.Additionally, his relationship with Commander Erwin makes them one of the best and most compelling duo's in the show.
Jiraiya - 'Naruto'
The Tale of Jiraiya the Gallant. One of the three Legendary Sannin, Jiraiya showed up in Naruto as the eccentric, womanizing Toad Sage that was primarily comic relief. He also became Naruto's new Sensei, teaching him the powers of Sage mode, the Rasengan, and enhancing Naruto's abilities greatly.
Jiraiya's infiltration of the Village Hidden in the Rain, and his subsequent fight with Pain, is one of the best arcs and emotionally intense battles in all of Naruto: Shippuden. Jiraiya's relationship with Naruto is so incredible and runs very deep, with Jiraiya also being the Sensei of his late father, Minato, the Fourth Hokage.
Whitebeard - 'One Piece'
The Strongest Man in the World. Not including the flashbacks that happen post-time skip, Whitebeard doesn't have a crazy amount of screen time. But his presence during the Battle of the Best is undoubtedly felt by everyone there. Even at his advanced age and failing health, Whitebeard is unparalleled in strength and feared by all.
Monkey D. Luffy never minces words, and doesn't care for others status or reputation, so his interactions with Whitebeard are unfiltered, shocking everyone around them, but earning respect from the Yonko. This leads Whitebeard to make Luffy the primary focus, as his crew protects him at all costs, so he can try to save his brother, and Second Division Commander of the Whitebeard Pirates, Portgas D. Ace.
Itachi Uchiha - 'Naruto'
Originally a primary antagonist, along with the Akatuski, in Naruto and Shippuden, Itachi's story developed into one of the most heartbreaking and tragic plot lines in the series. Forced to choose between his country and his family, Itachi slays the Uchiha clan, sparing only his little brother, Sasuke.
Itachi drives Sasuke down a path he did not intend, making his decisions all the more tragic. Additionally, Itachi was just 13 years old when he was forced to do these things by Danzo. The revelation that he loved his younger brother, and was forced into the life he had, make him one of the most compelling and popular characters in anime.