Some friendships are so strong that not even death can split them apart.
This trope also applies to family relationships.
Compare to Reincarnation Romance for romantic variants.
- Familial love was the reason Orochimaru sought immortality. He loved his parents dearly, and when he lost them he was absolutely broken. When he learned about reincarnation, he decided to look for ways to make himself live forever so he could meet his parents again when they reincarnate. Unfortunately, Orochimaru eventually became so consumed by staying alive and collecting and creating rare and powerful Jutsu that he completely forgot the original purpose of his research.
- Best friends Naruto and Sasuke are reincarnations of the Sage of Six Paths' sons Ashura and Indra.
- According to the Arcadia of My Youth movie, Captain Harlock and his Best Friend Tochiro Oyama's WWII-era ancestors have also been best friends for the short time they fought together.
- In Cross Ange, when Ange encounters Salamandinay for the first time, both girls are overwhelmed by a stream of what appears to be genetic memories, showing them that, in their past lives, they have almost always been fast friends — except when they were lovers.
- A central theme in Spirit Circle. As main character Fuuta traversed through his past lives, he discovered that everyone in his group of friends all also had close relationships with him in their preincarnations, although the exact relationship varies. For example, his friend Nono went from simply a girl he met just before death during Vann's life, then a servant in a foreign country in Flors' life, and in subsequent lives she became an adopted daughter, then a crush, and currently she's someone who has a crush on him. This extends even to minor characters. Vann's neighbour farmwoman, for example, later becomes Lafalle's subordinate.
- Invoked and the cause of a lot of drama in The Legend of Sun Knight. Each of the Knights chooses a successor and trains him to be as close as possible to the original knight, including in personality, abilities and even friendships in public. Thus the current Sun Knight spends hours on makeup everyday to maintain his bishonen appearance, can't flirt with girls because the original was a Chaste Hero, and has to pretend to be best friends with Earth Knight (they both dislike each other and gladly play Moment Killer to each other) and enemies with Judgement Knight (they're actually best friends, bonding over the difficulties of the role they have to play) to remain true to the original Sun Knight's relationships. And this is in addition to the politics and Interservice Rivalry they deal with on a daily basis.
- It's revealed in a side story of My Next Life as a Villainess: All Routes Lead to Doom! that Katarina's friend Sophia is actually the reincarnation of Atsuko, who was her best friend in her previous life. Unlike Katarina (who is fully aware of who she used to be), Sophia's Past-Life Memories only come to her in quickly forgotten dreams or the occasional voice in the back of her head, so both of them remain unaware of their past relationship. There's also some overlap with a Reincarnation Romance, since Sophia is in love with Katarina (though Atsuko wasn't).
- Referenced in the Hyrule Warriors fic In Sotto Voce. Impa and Zelda currently have a Reincarnation Romance but it's noted that in other lives they've had variety of bonds, including a platonic friendship and even mother/daughter-like relationships.
- While 'reincarnation' hasn't been explicitly invoked in the Frozen fic "Lady in White: Legacy", the fact that Samantha 'Anna' Reinhart is initially mistaken for Anna by the now-immortal Elsa makes it clear this trope is intended to apply.
- In the fanfic Dragonshyness, Pinkie Pie is well aware that Twilight Sparkle is a reincarnation of G3's Minty, who was the best friend of Pinkie's earlier self, G3 Pinkie Pie (in a world of asexual immortals in which "best friend" was the emotional equivalent of One True Love). Pinkie is not only willing to exhaust herself to save Twilight Sparkle, she will stand by her even when Pinkie's own powers are exhausted and she is close to defenseless.
- A Tale of Two Rulers: Undead Child Skull Kid and Eternal Hero Link have known each other for thousands of years and consider themselves best friends, although it's complicated by the fact that Link starts out each incarnation without his Past-Life Memories and only regains them piecemeal.
- What Dreams May Come in the end, both Chris and Annie choose reincarnation over heaven and hell, and we end with them meeting for the first time, all over again.
- A Dog's Purpose is about a dog who goes through various lives Desperately Looking for a Purpose in Life. In his second, and most influential, life as Bailey he meets a boy named Ethan and becomes his best friend. Bailey died of natural causes years later. Two lives later, he reunited with Ethan, who himself is now a senior. Ethan never realizes that Buddy is Bailey (the film changes it so that he does). The closest is when he's dying of a stroke and mistakes Buddy from Bailey.
- Technologically mediated form in Nexus Nine, after inheriting the Rheum chip from Darius Rheum, Mazel connects with his old friend Shep Bataille and attempts to continue their friendship.
- Charmed: In an episode with flashing back to previous lives, its revealed the entire cast have been reincarnated several times and always are draw together, sometimes as enemies though, so it may not count.
- Star Trek: Deep Space Nine: Benjamin Sisko has a best friend named Jadzia Dax. He's been best friends with her ever since The Symbiote inside her was in a different body: Curzon Dax. After Jadzia's death, the Dax symbiont is placed inside of a new host, Ezri, and the friendship with Sisko continues.
- The X-Files, "The Field where I Died": Agent Mulder under hypnosis recounts that he, his sister, Scully, one-off character Melissa and Cancer Man have been reincarnated into each other's lives over several lifetimes. Cancer Man is always evil. Melissa is Mulder's soul mate in all his lives. Agents Scully and Mulder are always tight and very close friends, sometimes one of them can be an authority figure (e.g. in one past life, Scully is Mulder's sergeant).
- The Australian sketch comedy Soul Mates centers on pairs of characters throughout history played by the same lead actors; the surreal opening sequence depicts their souls singing about how...
And we'll be best friends forever
In a mostly platonic sense
This is a love that never ends"
- "Old Souls" by Heather Alexander is about feeling deja-vu around certain people.
- Discussed in Higurashi: When They Cry. When Shion is performing what she thinks is going to be a Heroic Sacrifice, she tells Keiichi to pass on to Mion that she wants to be twins again in the next life.
- Jacopo and Maria are mutually reincarnated thrice in The House in Fata Morgana. While Jacopo indirectly causes Maria's death in their first life and outright shoots her in their second, their relationship finally stabilises in their third life, where they hit it off and become Vitriolic Best Buds shortly after meeting.
- Everyman Hybrid: Evan, Vinnie, Jeff and Stephanie are all stuck in what fans have termed "iteration cycles", where their lives are on constant repeat until they reach a desired result as planned by HABIT. In addition to being friends throughout the show, in ignorance of their constant reincarnations beyond some confusing Revealing Continuity Lapse shenanigans, it was discovered through voice recordings made by different iterations of Vinnie that he was still friends with Evan, Jeff and Stephanie in at least two different timelines, despite those timelines taking place in entirely separate decades from the current one, and a previous mention of "the universe not wanting them together".
- Avatar: The Last Airbender:
- Avatar: The Last Airbender: Gyatso, the Cool Old Guy monk who raised Aang, is revealed to have been a good friend of Aang's previous incarnation Roku.
- In The Legend of Korra, the next avatar after Aang, Korra has been friends with Aang's wife Katara and their now-adult children since Korra was a young child. Korra later meets Aang's friends Zuko and Toph, and is mentored by the latter.