Friendships in many anime are portrayed as being integral to the protagonists' lives. Many anime heroes rely on friends and family to get stronger, to be inspired, and to defeat the villains. But what happens when these characters lose a loved one? What can it do to characters who rely so much on their support and presence?

RELATED: 10 Anime Characters Who Became Evil Because Of Love

Some heroes cannot handle the loss of their loved ones. Whether they die, are taken away, or are seriously injured, this loss turns them down the path of evil.

10 Naruto: Shippūden's Obito Went Bad After Watching Kakashi Kill Rin

Obito 4th Great Ninja War

When Obito Uchiha lost Rin Nohara, seeing her die at the hands of his best friend, Kakashi Hatake, he gave up on any dreams he had of being a good shinobi. Madara Uchiha then manipulated Obito into becoming truly evil, telling him that there was a way for him to be reunited with Rin.

Of course, this was not the whole truth, and Obito would follow the path of evil for nearly two decades. He only realized the error of his ways when Kaguya Otsutsuki was brought back and the entire world had to engage in a battle that would solidify their fates.

9 Also In Naruto: Shippūden, Nagato Formed The Akatsuki After Losing His Blood Family & Then His Found Family

Nagato looks down sadly and contemplates

As a child of war and an orphan of the tumultuous Hidden Rain Village, Nagato saw a lot of horrific things in his lifetime. He lost his family, but he found a new one in Konan and Yahiko. They created the prototype of the Akatsuki that fans know from the Shippūden series.

Over time, however, Nagato lost his comrades, and he and Konan were left to pick up the pieces. Thus, Nagato formed the evil version of the Akatsuki and sought to destroy the world to bring peace to it. His misguided ways were informed by the loss of his family and friends, as anyone who has seen so much loss would have a darker worldview.

8 Gendo Ikari Wanted To End The World Because He Missed His Wife In Evangelion

Gendo Confesses To Shinji In Evangelion Thrice Upon A Time

Gendo Ikari started the Eva programs and worked with a shadowy organization to bring about another calamity, the Third Impact (a sequel to a horrific cataclysm that occurred in Antarctica). His primary motivation was the love of his late wife. When Yui, his wife, passed, he became obsessed with finding a way to reunite with her.

Gendo's love for his wife was twisted, and it corrupted every other relationship in his life, from those with his coworkers to the one he had with his son, Shinji Ikari. Needless to say, much of the tragedy in the series could have been avoided if Gendo had been to therapy.

7 Dracula Vowed To Exterminate Humans Because His Wife Was Murdered By The Church in Castlevania

Dracula sneering In Castlevania

Another anime villain who had a tumultuous relationship with his son and could have benefited from therapy is Castlevania's own Dracula Tepes. His wife, Lisa Tepes, was murdered by the church, burned for witchcraft and heresy. Dracula was understandably distraught and angry. So he vowed to exterminate human civilization.

RELATED: 10 Anime Characters Who Became Good Because Of Love

Dracula was finally stopped by his son, Alucard, when he teamed up with monster hunter Trevor Bellmont and Speaker Sypha Belnades. Eventually, Dracula saw how his grief over the loss of his wife had changed him, and he let his son kill him.

6 Isabella Resolved To Be A Mama When She Lost Leslie In The Promised Neverland

Promised Neverland S2E9 Isabella

Isabella, like all of the characters in The Promised Neverland, was born and raised in a world that was extremely violent, dark, and oppressive. It was a world with no escape, or at least no perceivable escape. She grew up as an orphan in the same system she now works in as a Mama, and when she did, she lost her best friend, Leslie.

She tried to escape, but in seeing the lack of hope, she resolved to survive to keep Leslie's memory alive. So, she became a Mama and perpetuated the same horrors she endured as a child. Other than death, though, there was little option. If she had not been around for Leslie's death, she might not have become a Mama.

5 Vicious Became An Antagonist Because Spike Stole His Girlfriend In Cowboy Bebop

Vicious looks down

Vicious was always evil in the way that he was a main player in a huge crime syndicate. So was Spike Spiegel. So, it is not necessarily that he became evil upon losing a loved one, but he certainly became a huge antagonist with a vendetta against the protagonist that fans know and love when he lost Julia.

Julia was Vicious' girlfriend. After he was shot, they took Spike in and nursed him, which was a kind act. However, Julia and Spike fell in love, and they ultimately betrayed Vicious, who had been Spike's friend.

4 Zeref Became A Dark Mage Thanks To His Brother's Death In Fairy Tail

Zeref from Fairy Tail

Zeref's status as an evil Dark Mage who destroyed the lives of countless people in the Fairy Tail originally stemmed from the desire to bring back his late brother. He tried to do the unthinkable, the taboo, so he was cursed with the Curse of Contradiction.

RELATED: 10 Anime Heroes Who Became Strong After Turning Evil

It was not his choice to become evil, but due to this curse, he was given no choice, and it was all because of the love he had for his little brother. Thankfully, love saved the day, as well. His curse was broken thanks to the love between himself and the legendary mage, Mavis Vermillion.

3 Gaara Was Bad Because His Mother Died When He Was Born In Naruto

gaara using sand in naruto

Gaara was not evil for the entire series, but he started as a villain with no concept of love and did not change his worldview until fighting with Naruto Uzumaki. Gaara's attitude made sense, though. He was a child who was imbued with a volatile demon and who lost his mother as an infant.

Furthermore, he was almost killed by the only person who showed him love, because his father put a hit on him. So, Gaara's villainy may not be acceptable, but it was understandable. Fortunately, Naruto convinced him to change his ways.

2 Attack on Titan's Eren Yeager Saw Too Much & Eventually Went Evil

Ichiko Wins Another Day In Good Luck Girl

Eren Yeager's problems started when the city was breached and his mother was killed by a Titan. From there, everything spiraled downhill, and he watched friend after friend die at the hands of not only Titans but also his supposed allies. By the end of the series, Eren had completely changed.

Eventually, he had seen so much death that his entire personality and goals had changed, and he became a true villain. he was responsible for so much death as well as being traumatized by so much death.

1 Keicho Nijimura Made Stand Users Because He Wanted His Monstrous Father To Finally Be At Peace In Diamond Is Unbreakable

Keicho Nijimura points

Keicho Nijimura's foray into evil was not because his loved one had died, but rather it was because he wanted his loved one to be able to die. Because of Dio and the events of Stardust Crusaders, his father had been turned into a monster who lived in pain and could not die. So, Keicho and his brother, Okuyasu, sought someone with a Stand who could finally put his father to rest.

Keicho created a lot of problems in doing this, however. He turned a serial killer into a powerful Stand user and caused a lot of grief for the Joestar family.

NEXT: 10 More Anime Villains Who Became Evil Because Of Love