The world of anime is filled with all kinds of siblings: ones who love each other, ones who hate each other, siblings who do a bit of both, siblings who didn't even know they were related, and characters with siblings who are such minor characters that the audience tends to forget about them. And they sometimes come in groups of more than two.

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But many anime series give siblings the main focus and let their relationship and the love between them be an important part of the story, if not the main focus of the plot. That said, even the closest of sibling pairs have their moments where they don't get along too well.

10 Ryuko & Satsuki Learn To Love Each Other Over Time(Kill La Kill)

ryuko vs satsuki in kill la kill

Ryuko & Satsuki are arch-rivals and blood enemies at the start of the series. But as the series goes on, the two show mutual respect for each other and both effectively begin to serve as main characters. While Ryuko, who wants to solve her father's murder, initially appears to be the heroine, Satsuki's true colors are eventually revealed and it turns out she's not as villainous as she appears and wants to avenge the death of her father and sister.

And her sister turns out to be less dead than she thought, considering she's none other than Ryuko herself. They still have a few issues to work out, but eventually join forces and develop a sibling relationship.

9 The Matsuno Brothers Have A Strong Bond (Osomatsu-kun)

Cast of Osomatsu San Season 1

There's power in numbers and these sextuplet brothers are no exception, even if they often find themselves getting into mischief. The Matsuno brothers are made up of leader Osomatsu, tidy Karamatsu, crafty Choromatsu, strong Ichimatsu, kindly Jyushimatsu, and carefree Todomatsu.

Generally, the six brothers get along relatively well, but they do have their moments of conflict, especially Osomatsu with his younger brothers. That said, even in a meta-sense, they can be beaten: their rival Chibita and acquaintance and occasional teacher Iyami proved popular enough to take over the twins as stars of the series. Of course, they also got their reboot, which showed what happened to the brothers as adults.

8 Ace & Luffy Have A Deep Connection That Survived Years Of Separation (One Piece)

Luffy Sabo Ace

There are all kinds of siblings and people do not need to share blood to consider themselves family. Adoptive brothers Luffy and Ace, both essentially being raised by Luffy's grandfather, Monkey D. Garp, were close as children, albeit after Ace initially being annoyed by Luffy, and still clearly have a connection even after years of separation. They are able to guess each other's moves in a fight, showing how well they know each other, and Ace has been shown to be both proud and protective of his younger brother even after becoming pirates.

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The two would also be revealed to have a third sworn-brother, Sabo, who Luffy even considers nicer than Ace and who even behaves as something of a mediator between the two. That said, when they were younger, both Sabo and Ace were willing to kill Luffy out of concern he'd expose their secret treasure.

7 Hiei & Yukina Care For Each Other In Their Own Ways (Yu Yu Hakusho)

Hiei holding Yukina in Yu Yu Hakusho.

This sibling pair is complicated by the fact that one-half of the siblings aren't entirely aware of their relationship, but they still show they care for each other in their own ways. The originally villainous Hiei arguably started his redemption arc by rescuing Yukina from Gonzo Tarukane, who kept her as a prisoner, although he keeps his identity a secret from her.

Born to a tribe of ice maidens, Hiei was taken from their mother and cast out, causing Yukina to wander the world and search for her brother. While normally kind-hearted and sympathetic, she does have a rather dark reason to find him: she wants him to destroy the other ice maidens, in revenge for what they did to their family.

6 Hikaru & Kaoru Hitachiin Share A Bond Like No Other (Ouran High School Host Club)

hikaru and kaoru ouran anime

For some twins, some people, including the twins themselves, get into the habit of treating them as a single entity and Hikaru and Kaoru are no exception. They even finish each other sentences. That said, joining the host club has helped them try to branch out as individuals.

Other characters have problems telling them apart in the series, but things are made a little easier on the audience since they have different voice actors in both the Japanese and English versions of the show. Another hint is the way they part their hair.

5 Satsuki & Mei Would Do Anything For Each Othe (My Neighbor Totoro)

Satsuki and Mei look at rotting wood

This pair of sisters are the stars of the film, My Neighbor Totoro, in addition to the forest spirits. Having moved to a rural area while their mother is recovering in a hospital, the two sisters soon meet a spirit that they dub "Totoro" and have various encounters with him.

Like most siblings, they have their moments of conflict, especially when the anguish of their mother's illness takes its toll, but the story proves the love between the sisters, especially as Mei goes missing during the film's conflict. Allegedly, the story is inspired by Hayao Miyazaki's childhood with his three brothers, shortening the siblings to two for story reasons and changing them to sisters to make it less obvious.

4 Sango & Kohaku Grew Distant But Have A Long And Complicated History (Inuyasha)

Sango & Kohaku (Inuyasha)

While Inuyasha and Sesshomaru eventually find themselves teaming up against Naraku, another sibling pair from this series has also had a complicated relationship: Sango and Kohaku. Both were raised as yokai exterminators until Kohaku was murdered by a demon and essentially revived by Naraku as a human puppet just to toy with Sango.

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Upon his return to life, he was initially unable to recognize his sister completely but did acknowledge some familiarity with her. Eventually regaining his memories, he tries to help his sister while still posing as Naraku's minion, such as secretly helping her at Mount Hakurei. Believing he caused Sango harm also brings about great mental anguish for Kohaku. In later years, they've initially seemed to have grown distant, with Kohaku admitting he doesn't visit her too often, but later goes on to be a mentor to her son, Hisui.

3 Edward & Alphonse Elric Know How To Play To Their Strengths As A Team (Fullmetal Alchemist)

Edward & Alphonse Elric (Fullmetal Alchemist)

Edward and Alphonse Elric have endured a lot together. A failed attempt to revive their dead mother caused Ed to lose his arm and Al his whole body, causing his soul to be fused to a suit of armor. Together, they go on a search for the philosopher's stone to recover what they have lost, all the while discovering truths about their world.

These two are a sibling team who knows how to play to their strengths: Ed might be the better alchemist, but Al is the better fighter. Essentially being a living suit of armor helps in that regard.

2 Ryūichi & Kotarō Kashima Protect Each Other (Gakuen Babysitters)

The cast of School Babysitters.

After losing their parents, Ryūichi and Kotarō Kashima are taken in by a rigid school chairman Yōko Morinomiya, who expects Ryūichi to work at the school's daycare center while staying with her, also allowing him to keep an eye on his younger brother.

Throughout the series, Ryūichi treats watching over Kotarō as a priority and is very protective of him. After all, he's practically the only family he has left at the start of the series. For his part, little Kotarō adores his brother, constantly tries to help him, and the sheer thought of someone not thinking the world of him is mind-blowing.

1 Tanjiro Does Everything He Can To Keep Nezuko Safe (Demon Slayer)

tanjiro anime

Tanjiro Kamado's family has been slaughtered, leaving only his sister Nezuko alive but at a price: she's turned into a demon. This starts off Tanjiro's quest to avenge his family and somehow restore his sister's humanity.

Showcasing their bond, Tanjiro is initially forced to carry Nezuko around in a wooden box until she develops the ability to survive sunlight. For her part, while her transformation into a demon initially cost Nezuko her mind, she still has enough memory to stop her from harming her brother, eventually viewing all humans as her family.

NEXT: 5 Anime Siblings Who Want To Kill Each Other (& 5 That Get Along Great)