In the world of Japanese anime, family plays a big role. Many protagonists' character arcs are shaped by their relationship with their parents and their siblings, and some family members are anything but supportive of their relatives. Some parents are downright abusive or tyrannical, and for that matter, so are many brothers and sisters.
In some cases, an anime character's worst enemy is not the supervillain or a criminal kingpin, but their own brother, and these brothers show no mercy. These anime brothers are total jerks either to their siblings or to their classmates or associates, or even all of them. Even token brother characters feel like saints compared to these cruel anime brothers.
Spoilers ahead!
10 Leon Bartfort Often Taunts His Sister (Trapped In A Dating Sim)
The isekai antihero Leon Bartfort spent his pre-isekai days grinding his way through an action otome game at his little sister's request, only to end up in that game's world for real. Soon, Leon's little sister got reborn there too, assuming the identity of a certain Marie. She was a selfish schemer and a total himedere.
Marie's brother, Leon Bartfort, was no better. He often mocked or annoyed her, and for that matter, he was a jerk toward almost everyone around him, and he enjoyed it. He took great pleasure in antagonizing all his pretentious classmates, including Marie, but he did show kindness to Angelica and Olivia, at least.
9 Illumi Zoldyck Sought To Control His Little Brother (Hunter X Hunter)
Gon Freecss has no brothers, but his friend Killua Zoldyck sure does, and Killua could tell Gon what a hassle it is to have an overbearing big brother. Illumi Zoldyck is a strange and creepy fellow who is loyal to his reclusive assassin family, meaning he's at odds with the runaway Killua.
Illumi even put a mental trap in Killua to control the boy's behavior to an extent. Illumi simply did not trust Killua to do the right thing, and thus he felt the need to manipulate and restrict Killua. Illumi felt totally justified in doing that, and he didn't regret a thing.
8 Sesshoumaru Looks Down On InuYasha (InuYasha)
The arrogant, white-haired demon dog Sesshoumaru is obsessed with claiming the mighty Tetsusaiga for himself, and he does not believe that his half-demon, half-brother InuYasha is worthy to wield it. This goes against their demon father's wishes, but Sesshoumaru doesn't care. It's all about what he wants.
Sesshoumaru slowly mellowed out over time, but overall, he's still a jerk of a brother who sees fit to look down on InuYasha and exploit or abandon everyone around him. It's true that Sesshoumaru is a demon, but not all demons are bad. Sesshoumaru should do better as a demon big brother.
7 Yuri Briar Is Hostile To Loid & Anya (Spy X Family)
On one hand, Yuri Briar is absolutely devoted to his lovely big sister Yor, and he is always protective and kind toward her. But now he's also a brother-in-law, and Yuri always shows his worst side to his brother-in-law Loid Forger and even Anya Forger as well.
Yuri loves his sister and is deeply skeptical of Loid and feels the need to aggressively protect Yor from him. Yuri is highly passive-aggressive toward Loid and Anya as a result, and might even show open hostility when his patience runs out. Yor, meanwhile, is aghast that her brother and husband are clashing so much.
6 Dabi Hates His Family (My Hero Academia)
Some heroic brothers and sisters are very kind, such as Tensei Iida and Tsuyu Asui, but not Dabi. He was born as Toya Todoroki, Endeavor's and Rei's first son, and he was consumed by his fire-based Quirk and presumed dead. Dabi now seeks revenge on his hated family.
Dabi is a coldly villainous person as a League of Villains member, and it only gets worse. Recently in the manga, Dabi/Toya battled his younger brother Shoto, and Dabi showed his sadistic side, including verbal abuse. This rogue Todoroki is determined to burn down everything that Shoto and Endeavor hold dear.
5 Light Yagami Didn't Love His Family At All (Death Note)
On the surface, the genius Light Yagami gets along well with his parents and little sister, but the other Yagamis have no idea how cruel and wicked Light had become as Kira. Light cared far more about his Kira kingdom than he did his family, and he even considered killing his father and sister to protect the notebook.
Even though Light never went through with that plan, it's still chilling that he would kill off his sister, Sayu, to foil Mello's plans. Light also held most of the people around him in total contempt, especially Matsuda and Misa Amane, and he was frustrated when his father Soichiro died. Not out of grief, but because Soichiro had failed to kill Mello with the notebook.
4 Ayato Kirishima Attacked His Sister (Tokyo Ghoul)
Touka Kirishima is a bit of a roguish antihero, but that's nothing compared to her vicious little brother, Ayato. Unlike his sister, Ayato fully embraced his ghoul nature from the very start and scorned humans as weak, while also mocking ghouls who sympathized with humans. And he wasn't afraid to get violent about it.
Ayato joined Aogiri Tree at one point, and he fought both his sister Touka and Touka's friend Ken on that group's behalf. He was totally lost to darkness, but later in Tokyo Ghoul:re, he was finally redeemed and started seeing things his sister's way.
3 Thomas Coleman Abused His Foster Brother (My Next Life As A Villainess)
Keith Claes' life was changed for the better when he was adopted into the Claes family and gained Katarina as a foster sister. But before then, Keith had been tormented by his brutal half-brother Thomas Coleman, and that made Keith's life a living hell.
Thomas was a self-centered and insecure person who looked down on his half-brother's heritage, so to protect the Coleman name, Thomas became abusive. Eventually, Keith was taken away from that terrible household, only for Thomas to kidnap him years later with Sarah's aid.
2 Raditz Is A Brutal Saiyan (Dragon Ball Z)
Son Goku has a brother named Raditz, and he's no hero. While Goku is humble and selfless as a Saiyan who protects the weak, Raditz has a mindset more akin to Vegeta's. He's a proud warrior who is quick to look down on others and torment the weak.
Raditz may have shown his brother compassion once or twice, but that's the exception. Otherwise, this Saiyan ranks among anime's worst brothers of all, and Gohan and Goten have no real reason to appreciate their Saiyan uncle at all. This is a part of their family they're better off without.
1 Fire Lord Ozai Abuses Everyone (Avatar: The Last Airbender)
Fire Lord Ozai was actually not first in line to claim the Fire Nation throne from his father, Azulon. The firstborn son, Iroh, was set to become the new Fire Lord, but after the death of Iroh's son, Lu Ten, Ozai claimed the throne instead and even had his new wife, Ursa, poison Azulon to get rid of him.
Ozai is thrilled to be Fire Lord, and he shares none of the glory with his much kinder older brother. In fact, Ozai now holds Iroh in contempt as a softie who failed to conquer Ba Sing Se, and it's clear that these royal brothers never reconciled, either. Even the generous Iroh is in no mood to make amends with his monstrous little brother.