Jean Kirstein is the cynical Jerkass to Eren's idealistic hero. The two immediately come into conflict due to their differing ideas, and nearly end up putting things behind them. That he ends up falling for Eren's beautiful, violently-protective foster sister results in him becoming a Green-Eyed Monster and adds further fuel to their rivalry. However, Jean ends up accurately predicting that Eren's lack of forethought would come back to haunt him and proves to be the better soldier of the two. It turns the whole trope on its head, however, in that Jean doesn't end up coming over to Eren's side because of anything the latter did, but rather through Jean's own personaltragedies and development into a promising young leader.
The series later introduces a darker Foil to the above, with the childhood rivalry between Jerk Jock Porco Galliard and idealistic Heroic Wannabe Reiner Braun. As children, Galliard's Brutal Honesty brought him into repeated conflict with Reiner and led to blows more than once. As Warrior Candidates, they competed to inherit the Armored Titan and become the 4th member of the team being sent to Paradis Island. Their relationship as adults isn't much better, with Galliard blaming Reiner for the death of his brother and convinced things would have worked out better if he'd won over Reiner. For his own part, Reiner accepts this criticism and neglects to tell him that Marcel rigged the selection process in Reiner's favor....to protect Galliard.
Sweden and Denmark in the past, with a history of wars rivaling England and France, over their competition for control of the Baltic and Scandinavian regions (with Denmark most often on the losing end). In the present, though, things have calmed down, and Denmark proclaims that he and Sweden are now the best of friends.
The Netherlands has warred in the past with Spain, who gave him the noticeable scar on his forehead during one of their conflicts. Netherlands also warred with Portugal in an attempt to dominate maritime trade and make Macau his own.
Russia and America during the Cold War. Though they're no longer enemies in the present, they're still rather tense and passive-aggressive toward one another.
A lighter example is Ladonia, who sees Sealand as this, due to the fact that Ladonia wishes to take Sealand's place as leader of the micronations. Sealand doesn't reciprocate, and instead is fond of Ladonia and calls him "interesting."
Czech Republic sees Hungary as this where spas are concerned, as she's adamant that her very famous spas are seen as the best in the world. Hungary doesn't reciprocate.
Bleach: Ichigo's had several over the years, but his most notable rival is arguably Grimmjow (who serves as his Evil Counterpart), whose hatred of him borders on obsession. What started as an attempt to outdo Ulquiorra eventually lead to arguably the most intense grudge between two people in the entire series. The animosity between Grimmjow and Ichigo finally reached a boiling point in the Hueco Mundo arc, where the two finally had an uninterrupted fight in which Ichigo won. He returns during The Thousand Year Blood War to aid Ichigo and the others in their attempt to defeat the ultimate enemyYhwach, if only to guarantee a rematch with Ichigo.
In City Hunter, Umibozu is Ryo's rival. During the story they're Vitriolic Best Buds or, when finding themselves on opposing sides, Friendly Enemies, but Ryo's American acquaintances revealed it's a fairly recent development and that they used to be Arch-Enemies.
Suzaku Kururugi. It's little more complicated than the norm though. Suzaku plays friendly enemies with Lelouch, due to their friendship but drastically opposed viewpoints. Though Lelouch is initially not aware, and feels quite betrayed when he finds out, he sort of understands Suzaku's views and situation, going so far as to save him twice, despite it. Up until the second season, where things get... generally more violent, and their respective actions, much less forgivable.
On the other hand, Kallen and Suzaku more easily fit the mould of the rival, with both being exceptional pilots, and the same ultimate goal.
Death Note: Light and L are classic examples, foils with similar traits, differing ideals and near-opposite appearances to offset their near-identical approaches to problems. They suffer from a serious case of Rivals Team Up under odd circumstances as well, though it both was and wasn't true teamwork.
Half the cast of Dragon Ball Z has had this relationship with Goku at one point or another, Vegeta being the most prominent example, with Yamcha being the first.
Hakuoh and Kokujo from Duel Masters, the former doing a total 180 in every aspect after Shobu beats him, while the latter never really stops being the rival, softening only the slightest bit.
Kenshiro had Shin and later Raoh as a primary rival in Fist of the North Star. His friendly rival/brother-in-kung-fu Rei had Juda as his.
Rin considers Haruka his rival in Free!. It's a little one-sided, as Haru doesn't like to compete and doesn't seem especially interested in beating Rin. However, when they were children, Haru was miffed that Rin seemed to "understand the water" more than he did. It is commented on later that Haru is actually more fired up when it comes to Rin, and by the time Rin and Haru reconcile, they've gone on to heatedly competing over silly competitions like catching crabs and who gets the better fortune.
Eas in Fresh Pretty Cure!, mostly toward the protagonist Love than the other Cures. Complete with pretending to be friends to try and sabotage their team from within and a Deconstruction of Becoming the Mask which amps up Eas' side of the rivalry then cranks up Love's end after the inevitable betrayal leading into a very personal duel where Love even told the other Cures not to get involved. This being Pretty Cure, friendship trumps everything and Eas pulls a HeelFace Turn after she and Love work things out.
Athrun Zala is Kira's rival in the original Mobile Suit Gundam SEED and probably his main rival overall. This is a unique example for the Gundam franchise in that they know a lot about one another. They were childhood friends and often find it difficult to fight one another. The show milks this dynamic for all it's worth, having Athrun attempt to capture Kira alive and having oodles of fun when messing around with the dynamic the two boys' love interests have.
From Mobile Suit Gundam SEED Destiny Kira Yamato and Shinn Asuka are rivals to each other. Although this case in interesting in that neither of them know anything about each other nor each others names. They meet once but say very little and don't know who the other is. This somewhat changes after Kira kills Stellar with the Freedom and Shinn's considered the Freedom (and it's pilot, Kira) to be his Arch-Enemy. In fact, once Shinn upgrades to Destiny, Kira doesn't even know he's the same pilot he's fought before, while Shinn only know the Strike Freedom as the upgraded version of Freedom and assuming they have the same pilot. So they are effectively faceless enemies to each other for their entire rivalry.
In Mobile Suit Gundam 00 Graham Aker is the rival to Setsuna F. Seiei. Interesting in that Graham is at first a typical mecha pilot, but it's in season two, after we've met him, that he becomes the traditional Char Clone. When the movie comes around Graham has come to understand Setsuna's perspective and prays for his recovery so they can both fight the oncoming alien threat.
Jerid Messa is Kamille Bidans's rival in Mobile Suit Zeta Gundam. There rivalry is definitely one fueled by revenge, and is actually more of a mutual hatred than just a rivalry, considering they both have taken the lives of many important people in the other's life.
Anavel Gato and Kou Uraki become rivals in Mobile Suit Gundam 0083: Stardust Memory. At first Gato considers Kou as nothing more than a rookie that's in over his head, but soon enough he recognizes him as a worthy foe after their duel and the destruction of the GP-02A and the GP-01Fb
Treize and Wufei are portrayed as rivals as well. They meet when Treize challenges Wufei to a sword duel, and after losing, Treize respects Wufei's honor, while Wufei has a begrudging respect for Treize's strength and a burning desire to defeat him. Their rivalry comes to an end with Treize dying with a smile on his face at Wufei's hands.
Played for Drama in Mobile Suit Gundam AGE: Asemu and Zeheart become this due to their shared highschool time together, yet got into different side of war: Asemu sided with Earth Forces, and Zeheart sided with Vagan, similar with Kira and Athrun's Gundam SEED example above.
In Gundam Build Fighters, Sei and Reiji have a few rivals, from Mao, Fellini, Nils, and Aila, but the only true rival for them is Yuuki Tatsuya, a.k.a. the third Meijin Kawaguchi.
In Gundam Build Fighters TRY, each of TRY Fighters' members have the rival in Celestial Sphere team: Sekai with Wilfrid Kijima, due to both of them are passionate Gunpla Fighters that respect each other as the Worthy Opponent; Yuuma with Saga Adou, due to the latter has humiliated the former in the Gunpla Battle so bad that make him trauma and not participate into Gunpla battling until two years later; and Hoshino with Shia Kijima, beside the Gunpla battle's reason, somewhat they are rivaling each other because both of them has attracted to Sekai.
Domon Kashu from Mobile Fighter G Gundam is interesting in that almost his whole Five-Man Band can be considered his rivals, even after they are corrupted with and later cured of DG Cells and join his team. The local Char, Schwartz Bruder does not count as a rival, as he serves more as a mentor.
Alucard and Alexander Anderson are this in Hellsing. Due to Anderson's humanity, regenerator abilities, and ridiculous levels of determination, Alucard views him as a Worthy Opponent and relishes every fight they're able to engage in, sometimes even overlooking his primary mission in order to fight him. And although Alucard visibly breaks when Anderson forsakes his humanity in a bid to defeat him, he still respects the priest in the end and understands why Anderson made the choice that he did.
Akira in Hikaru no Go: The series premise makes turning evil and/or the need for a rescue, embarassing or otherwise, highly unlikely. Mass quantities of Foe Yay are used, seemingly to make up for it.
IGPX: Immortal Grand Prix: When Takeshi Jin was hired by Team Satomi, incumbent pilot Riven felt put out by the decision, and the two were bitterly at odds until Riven finally decided to quit and join rival Team Sledgemama. As it turned out, Takeshi connected with Riven much better as a rival, and they've since become much friendlier.
Takahashi Keisuke (specifically, because he best fits the "intolerable ass" requirement), and at least half the cast of Initial D.
In Kitsune No Yomeiri Kanon the Tanuki considers herself to be Kyouka's rival and tries to defeat her in everything possible whenever they meet but always fails.
Magical Girl Lyrical Nanoha A's had one Wolkenritter to match up against each of the main combatants on the cast; Signum vs. Fate, Vita vs. Nanoha, and Zafira vs. Arf. Signum and Zafira were more like Worthy Opponents to their respective counterparts, but Vita plays the trope straight.
Magical Girl Lyrical Nanoha Strikers has Agito vs. Reinforce Zwei until the former is adopted by the Yagami family and they have developed a friendly Sibling Rivalry. Also downplayed with the unspoken rivalry between Nanoha and Teana—despite them starting off teacher and student, respectively, they quietly compete over who is the best sharpshooter of their generation (Nanoha is only three years older), if the mock battles in ViVid are any indication. Also, over being the bigger influence on Subaru.
Magical Girl Lyrical Nanoha Vivid had Einhart to Vivio, and she was the Unknown Rival to Ixpellia in the beginning of the season, but Einhart has become a Friendly Enemy and the best friend of Vivio and she has given up on Ixpellia, who lies in a coma anyway. Many of the Inter-Middle Championship participants have a strong rivalry to each other. Harry vs. Victoria, Els vs. Harry, and many participants are rivaling Sieglinde, especially Micaiah has the strongest resolve to defeat her. Vivio gained another rival of the Friendly Enemy type, Miura Rinaldi, who has a similar role as Vita and Signum to Nanoha and Fate, respectively.
Magical Record Lyrical Nanoha Force has the Hückebein Family, who are opposing Special Duty Section 6. Among the Hückebein members who are rivals to several SDS6 members, there are Curren vs. Hayate, Veyron vs. Thoma, Cypha vs. Signum, and Arnage vs. Isis. It also looks like there will other up-coming rivalries between DeVille and Fate, and Rosalia and Lily.
Tension flared between her and Yan-Min, right from the start, due to the latter calling Maken-ki weak. So Azuki dared her to prove it. Yuuka kept them from fighting, but they eventually traded blows during the Venus arc. While Azuki emerged the victor, she later admitted it was only because Yan-Min had held back. So she asked her to return to Tenbi so they could have a proper rematch.
Mazinger Z: Boss was The Rival from The Hero Kouji Kabuto. He was jealousy of Kouji because he was a better bike rider AND Sayaka had a crush on Kouji. The first thing he did when they met was picking a fight with him. However, as the plot and Character Development marched on, he slowly grew to respect him, and they eventually became friends (Boss still tried to compete with Kouji for Sayaka's heart, though). Also, in many Super Robot Wars games Kouji is rivals with Asuka Langley Soryu. The two of them always but heads. It is amusing, since she would be more liable to antagonize Tetsuya (both of them are two prideful Ace Pilots -Broken Aces, actually- can not stand losing).
Great Mazinger: Boss became again The Rival of The Hero -in this instance, Tetsuya Tsurugi- in the sequel. Boss could NOT stand Tetsuya, neither his arrogance (pretended arrogance, in fact; but Boss did not know that) nor Jun was infatuated with him. On the other hand, Tetsuya found Boss annoying, and he certainly did not care for Boss stalking Jun and showering her with unwanted attention. Tetsuya's true rival was Kouji, and when Kouji returned to the series, they got a very heated relationship. Kouji wanted to be friends or at least partners, but Tetsuya got very jealous and paranoid. He was an orphan kid with a huge Inferiority Superiority Complex, plenty abandonment issues and no self-esteem whatsoever, and he regarded Kouji like a threat would steal his father from him, take away his reason to exist, and replace him. Geez, he even accused Jun from wanting replacing him with Kouji (in spite of Jun barely knew Kouji and she had spent the whole series trying Tetsuya noticed her). He was ALWAYS arguing, bickering and fighting with Kouji, wether they were discussing tactics or battling the enemy.
UFO Robo Grendizer: Minister Zuril saw The Hero Duke fled like his rival, since he was in love with Rubina, King Vega's daughter, and Rubina was in love with Duke. Nonetheless, Duke regarded him like another Vegan commander he had to defeat.
Sasuke floats in and out of this role. Kishimoto actually stated he read up on the archetype in various manga when making him. Sasuke's entire creation was based on the fact that Kishimoto's editor said that Naruto needed a rival. Guess the fangirls should be grateful for this trope.
Then there's Sakura and Ino, though their rivalry has toned down a lot in Shippuden.
During the Chunin Exams, Rock Lee added three other ninjas as his other rivals besides his teammate Neji: Sasuke, Gaara and Naruto.
Also Guy and Kakashi, although this is arguably one-sided and usually Played for Laughs. Rather than knock-down, drag-out fights, it manifests itself in Guy challenging Kakashi to various dares or contests.
A hilarious case where creator Eiichiro Oda sees the Pretty Cure series as a rival due to his young children liking it more than One Piece. He vowed to take it down.
One could argue this for Luffy and Smoker, though it isn't so much as competing over anything as it is Luffy trying not to get caught by Smoker and get thrown into Impel Down.
A better example would be the Eleven Supernovas (a group of eleven rookie pirates, including Luffy and Zoro, with bounties of over 100 million who reached the end of the first half of the Grand Line at the same time) to each other; Eustass Kid and Trafalgar Law in particular are introduced as rivals to Luffy (although, in light of Law's alliance with Luffy, the two of them seem to have a relatively Friendly Rivalry at this point).
There's also Zoro and Mihawk, to the point that Mihawk trained him specifically for the job.
Assassins Jabra and Lucci are fierce rivals, despite both being former associates as members of C9; it's not their fault, however. Lucci has consumed the Zoan Neko Neko no Mi Devil Fruit (the Cat-Cat Fruit) while Jabra's is the Inu Inu no Mi or Dog-Dog Fruit. The opposing natures of the two Fruits compel them to oppose each other as a cat and dog would.
Gary (Motherfucking) Oak is Ash's Rival. In the anime he kept the rivalry until the end of the Johto saga, when he was defeated and pursued a different career, but he has since returned on a couple of occasions to help Ash and company, and is more of a Friendly Enemy than anything else.
The Hoenn arc was the only arc Ash himself went without a direct rival, although during The Hoenn League he went up against Morrison, who was much like Ash in his demeanor, and the two had a good battle.
Ash later met Barry, who is a borderline ditz. Nevertheless, their rivalry is fairly friendly and Barry became a fan favorite. It also helps that he Lampshades most of the tropes/traditions in the show.
Bianca, Stephan, Cameron, and Virgil are also introduced in this saga as rivals for Ash, the former two gaining more story and focus as rivals later on. Stephan and his Sawk even get their own rivals during the Clubsplosion arc.
During the first part of the XY series, Ash's main rival was Tierno, a Dance Battler whose "rhytmic battle style" Ash tried (and failed) to replicate. Tierno is noticeably an Ascended Extra, as he is probably the least notable rival in the XY games. During the second half of the series, however, Ash meets a young trainer named Sawyer, who actually looks up to Ash and makes it his goal to surpass him, a nice inversion of how Ash's rivalries regularly play out. Ash also develops a competitive rivalry with Alain, the protagonist of a side-story of the anime, who is interested in battling Ash and his Greninja's unique Super Mode. Alain, who is normally The Stoic, enjoyed battling Ash so much that he bothered to collect the 8 Gym Badges to participate in the Kalos League just so he can fight Ash. Ash, in turn, considers Alain the absolute bar to pass.
Starting in Hoenn, with the introduction of Pokemon Contests, Ash's female companions were also given rivals of their own.
May had Drew, who was better than her and could be arrogant but was ultimately friendly and wanted her to improve, and Harley, an angry, bitter Coordinator who declared her his personal enemy because she said his cookies were "Not bad" instead of the best thing she'd ever tasted. In a way they could be foils of each other, as they share a green/purple color theme, each primarily use a grass-type Pokemon, and have some degree of feminine traits (in Harley's case, he's full on camp).
Dawn got her childhood friend Kenny, who started shortly before she did, chose the same starter (though he evolved his, while her Piplup chose not to evolve), and started showing romantic interest in her she didn't return; Zoey, a seasoned Coordinator who was willing to calm her down and help her improve from the very start and won the Grand Festival; and Urusla, an egotistical Coordinator who tried to unsettle Dawn outside of competition to weaken her.
Unova didn't have Contests, but with the amount of additional battle competitions they had, everyone got a rival. Cilan got Burgundy, an up-and-coming (in her mind, at least) Connaisseuse who insists he insulted her and wants to defeat him as not only a trainer but a Connaisseur. Iris got Georgia, a somewhat gruff and self-proclaimed "Dragon Buster" who chalked up any losses she received to "It doesn't count. It wasn't against a dragon."
Kalos brought back the Contests- well, in a new form called Showcases. Serena got Miette, who actually became her rival before Showcases were introduced and also teased her about competing for Ash's affection (though she never showed any real interest in him, it was always aimed at Serena); Shauna, from the games, who is a step ahead of her but always helpful and encouraging; and Nini, who's also friendly. In fact, all three arrive at Master Class exactly when Serena does, helpfully (and playfully) announce that they've been her rivals, and as they're eliminated from the competition, ask Serena to carry on for them. Altogether, the rival scene from Kalos was a much friendlier afair, with Jessie being the closest to a malicious rival (ripping Serena's dress once just before she had to be onstage), but in that case, that was entirely one-sided, with Serena not even really being aware of her and their "rivalry," much less her feud.
Pokémon Adventures has Red and Green/Blue, mirroring the video games as well as Ash and Gary. They aren't ever explicitly hostile to one another, but are disdainful of their respective training techniques: Green thinks Red is airheaded and impulsive, relying on luck to win, while Red thinks Green is overly harsh and uncaring towards Pokemon, seeing them as simple tools. In the end, they wind up learning from each other (Red becomes calmer and more strategic, Green becomes more openly friendly with his Pokemon), and the two are Fire-Forged Friends as of the Pokemon League battles.
Red: Someone once told me that you have to know your limits! *recalls his exhausted Pokemon* Green: Heh. And someone once told me that there is no victory in defeating a weakened opponent. Choose your next Pokemon, Red!
In The Prince of Tennis both Sanada and Atobe start out as formidable, intimidating opponents. Along the way they earn the main team's respect to a degree, and in the last match, they help the main character regain his memories so he can face his last opponent (who happens to be Sanada's captain).
Ryoga is easily Ranma's foremost rival and closest competitor (as seen here) throughout the series. They've fought several times (excluding minor tussles) and the outcome, while almost always with Ranma being the victor, are usually close. Ranma openly acknowledged Ryoga as his rival, during the "Mark of the Battling God" arc, and has also acknowledged that few could force him to fight seriously, or push him as hard as Ryoga can.
One-time manga character Asuka Saginomiya, "The White Lily", is Kodachi Kuno's rival. She IS Kodachi, just in a different color. She actually manages to top Kodachi in terms of hamming it up by carrying around a large picture frame with lilies tied to her back so she can pose.
s-CRY-ed is largely built around the rivalry between brash, free-spirited Kazuma and stoic, duty-obsessed Ryuhou. In other series it's usually The Power of Love that can never be extinguished and can overcome any obstacle; in s-CRY-ed it's Power of Hot-Blooded Macho Rivalry instead. It's a notable example for just how much effort is put into developing their rivalry: at first it's simply because Kazyma and Ryuhou piss each other off, but gradually, even as their viewpoints and personalities change and develop their rivalry simply intensifies over time rather then ever really reconciling, and the series ends on their climactic final battle. Amusingly, in one episode a character with the ability to write a script that everyone must then follow as long as they're in it attempts to have the two reconcile in a friendly sparring match, his story ending in them becoming friends after working through their rivalry. It completely backfires, as Kazuma hates Ryuhou so much that just "fighting until they turn into friends" ISN'T enough for him, and it breaks the script and reality re-asserts itself.
Soul Eater has Ox claiming himself Maka's rival (only academically speaking), and Black Star sees himself as Kid's. Gopher appears to see Maka as his rival for Noah's attention, much to the girl's bewilderment upon first meeting the guy out to kill her with extreme prejudice. He takes the same attitude towards Kid who, like with Black Star, is simply not bothered.
Touch has Akio Nitta to Kazuya Uesugi and later Tatsuya Uesugi, Isumi Nishimura to Nitta (one-sided) and Takeshi Yoshida to Tatsuya Uesugi, also one-sided.
Ultra Magnus to Optimus Prime in Transformers: Robots in Disguise, as he feels he should have gotten the Matrix. He never turns evil, despite Megatron's best efforts.
Seto Kaiba from Yu-Gi-Oh! practically defines The Rival in this franchise.
Yu-Gi-Oh! GX has Jun Manjoume, a partial Expy of Kaiba, who serves as Judai's rival. Later, he gains a second rival (also a partial Expy of Kaiba, though utilizing different aspects of his personality) in Edo Phoenix. And for a few episodes Hell Kaiser could also count as a rival to both Judai and Sho. Also a Kaiba Expy, even using what is in its core a Cyber version of Kaibas deck.
A far more dangerous example in 5D's: three of the Dark Signers opposed one of the Signers for personal reasons. Kiryu to Yusei, Carly to Jack, and Misty to Aki. However, this was always due to their misinterpreting of past events (and Blatant Lies told to them), and each case ended with a truce called.
This continues in Yu-Gi-Oh! ZEXAL. Shark was Yuma's first rival, later becoming a Friendly Enemy and occasional ally. Kaito is another rival and might be considered an Expy of Kaiba, but had much darker motives and could not be considered anything more than a Well-Intentioned Extremist until the end of the first season. (Kaito usually considered Astral to be more of a rival to him than Yuma was.) Shark regains his status as the main rival in the last arc of ZEXAL II.
Reiji to Yuya in Yu-Gi-Oh! ARC-V. Unlike most other rivals who got befriended by the heroes, Reiji creates and leads The Team without befriending The Hero, and they still have a hostile relationship and Yuya has no other choice but to follow Reiji and his Lance Defense Soldiers to see his Love Interest again. It's until much later in the second season where Yuya finally begins to trust Reiji, but at that point, their rivalry is almost non-existent due to both of them on the same side.
The first is Brago, who is called "the demon to beat" by Kiyomaro. Not only is he one of the Four Demon Prodigies, the strongest in the generation that only the adults could defeat, he and his partner, Sherry, are the ones who seek out Gash and Kiyomaro and tell them about the battle in the first place before challenging them. It's only due to Sherry seeing Kiyomaro as a good guy at heart that they didn't have their book burned. As a point of reference for exactly how well Brago fits this trope, he placed second in the battle. To put it more plainly, he and Gash were the last ones standing out of all 100 demons.
Vincent Bari is also noteworthy. A powerful demon on his own, but he didn't have a true motivation in mind before he fought Gash; while he won the battle with them, Gash's willpower intimidated him so much that he decided to spare them until he was that strong. Fast-forward a couple of arcs to when he reappears, having defeated Elzador, another of the Four Prodigies, in a very close battle. That experience gave him will to match Gash's, and he's shown to be frighteningly strong. While he ultimately decides to pull a Heroic Sacrifice to help Gash and his friends, he's acknowledged as having enough will to rival the king.
In Kaitou Joker, Spade is The Rival to Joker and proves from early on that they're equals in terms of theft and gambits.
In Teasing Master Takagi-san the protagonist has an adorable "war" going with his cute classmate, with each of them trying to get the other to blush and react to their antics. She always wins these little contests.
Cage of Eden Yarai considers Akira to be his rival, though the two are on much better terms than many other anime rivalries. Segawa even points out that Akira is Yarai's first real friend, and that's why he can't kill him, even with Nishikiori's threat to let Kurusu die hanging over his head.
In My Hero Academia Midoriya starts gathering these as quickly as a Harem hero gathers their Unwanted Harem. Bakugo, Uraraka, Iida, and Todoroki all begin to see him as a rival whom they must pit themselves against in order to grow.