My Hero Academia explores many fun and/or complex themes of superhero mythology, but one of the biggest recurring motifs in the series is no doubt that of rivalries. There's the central rivalry between those two brothers that would manifest the power of One For All and its dark counterpart, which evolved into the epic rivalry between All Might and All For One. There are also big rivalries in the hero world itself, like the one between All Might and his pro hero competitor Endeavor. However, the most famous rivalry in My Hero Academia is no doubt the one between Izuku Midoriya and Katsugi Bakugo.
The "Deku vs Kacchan" rivalry has driven My Hero Academia since the first chapter. It's spawned endless fan theories as to how this subplot of the series will play out, and what major ramifications it will have. Fans of Boku Hero No Academia are plenty sensitive when it comes to the question of where Izuku and Bakugo's rivalry will lead, with no clear answer (yet) in sight.
So how will My Hero Academia handle the Deku vs. Bakugo rivalry? Here are several interesting ways it can play out:
The easiest and most obvious thematic parallel would be having Deku and Bakugo become the next generation of the All Might / Endeavor rivalry, as the competing top heroes of the Pro Hero world. Bakugo certainly has the that explosive (pun) sort of Endeavor personality, while Deku very much echoes the story of Toshinori Yagi becoming All Might. An easy resolution to this major series plotline.
This is the theory that makes quite a few My Hero Academia fans upset; but then again, this series is marked by enough deep tragedy that it warrants consideration. At this point in the series (the manga and/or anime version) it seems far-fetched that Bakugo would willingly turn to evil - but his willingness isn't necessarily a requisite. MHA has already shown characters like Tomura Shigaraki and (recently in the manga) Kurogiri were once figures with close ties to the Pro Hero world, before being taken and twisted into major villains. If the League of Villains ever gets its hands on Bakugo again, whose to say the same couldn't happen to him? Facing a true villain version of Bakugo would be a major spiritual loss for Deku - even if he survived.
If My Hero Academia wants to tell the story of how a younger generation improves upon the previous one, then instead of Izuku and Bakugo becoming the next All Might/Endeavor, or hero/villain rivals, they could unite and become an unstoppable team. Truthfully, the manga has already started leaning that way, as Izuku, Bakugo, and Shoto Todoroki have improved their respective quirks and team coordination while doing work study under Endeavor.
The mystery of the One For All quirk has been unfolding in My Hero Academia since the start. The latest chapters of the manga have revealed the powers' history and how its process of being passed on works. Without dropping any spoilers, the new My Hero Academia: Heroes Rising movie is also said to explore some inventive applications of One For All. Since the power is too much for Izuku's body to handle - and not even All Might was able to fully master it, maybe that brotherly rivalry that began the tragic history of All For One vs. One For All gets solved when two rival "brothers" find a way to share the power?
This would be a major twist in My Hero Academia's story that would certainly elicit an impassioned reaction from the fandom: What if Bakugo became the holder of One For All? That change wouldn't require Izuku's death, necessarily: Deku could become injured like All Might was, or could have some other physical or psychological reason for needing to give it up. Given where the anime is now, there's x-factors like Overhaul's quirk-canceling bullets that could come back into play, at any time. Like Mirio, Izuku may lose his power for a stretch of time, and it would be a storyline of major growth for both him and Bakugo, if Deku went back to being a quirkless fanboy, and Bakugo had live up to the noble legacy of One For All. In fact, this outcome is already one of My Hero Academia's most prominent fan theories...
My Hero Academia gets compared to Dragon Ball quite often - with good reason. Izuku's leveling up with the One For All power is a lot like Goku and/or Vegeta's power-up transformation process, complete with "Super Saiyan Deku" moments when Izuku has tapped into One For All's deeper powers. If there's going to be a moment where Deku truly 'Goes Super Saiyan' and reaches that next level of power, then there only two real tragedies that make it happen: the death of All Might, and/or the death of Bakugo. While Kacchan is a fan-favorite for sure, his death could serve major purpose in the series.
This would arguably break the My Hero Academia fandom and shock the manga/anime world. It's a rarity (outside of Hitchcock) to have a major movie or series pull a protagonist bait -and-switch - but this is anime, and anything can happen. If My Hero Academia ever killed off Deku, then Bakugo would be the one to take up his late friend's mantle - whether that meant inheriting One For All, or just carrying his ideals forward as Bakugo and Class 1-A become the next batch of Pro Heroes.
For those unfamiliar with the My Hero Academia juggernaut, the series was created by Kohei Horikoshi and has been running in Shueisha's Weekly Shonen Jump since July 2014. The story follows Izuku Midoriya, who lives in a world where everyone has super powers, although he was born without them. Dreaming to become a superhero anyway, he's eventually scouted by the world's best hero, All Might, and enrolls in a school for professional heroes. The series has been collected into 15 volumes so far, and has been licensed by Viz Media for an English language release since 2015.