The character most likely to die in any major series, regardless of genre, is the hero's best friend, girlfriend or most beloved relative, as he or she is a prime target for the bad guys.
Speaking both literally and metaphorically, the most dangerous place that one can be is also the place that seems the safest: right next to the hero. It's not just spatial, but emotional; the best friend, significant other, little sister and sidekick of the hero are all deeply at risk because that leaves them as prime targets for the villains, and their deaths act as fuel for Heroic Resolve, Unstoppable Rage or simply the sadness of losing such a beloved character. You die, the hero gets mad, kills the baddie, and everyone wins... except you. And that's assuming that he even remembers you next episode.
In any case, the death of such a character is meant to sadden the audience more than any other act of evil — either a standard Kick the Dog moment or a full-on crossing of the Moral Event Horizon — that the villain does. If not to make a Heroic Resolve, then the point is usually to encourage character development.
These friends are usually universally likable, and always there for the hero. They will never betray the hero, always know what to say, and basically help the hero in any way they can, the more eagerly the better. Basically, the closer to the hero the character is shown or implied to be, and the more the audience connects with the character, the lower his life expectancy. Whether it be a Heroic Sacrifice, or simply being caught in the crossfire, these characters are easily brought down by their determination in helping their friend. Bonus points if the character, while being the hero's best friend, is also The Rival.
Note that this is a character type similar to The Mentor, though a friend rather than mentor. For the act of actually killing the friend, see Stuffed into the Fridge. Similar to Obi-Wan Moment and Retirony. Often uses Sacrificial Lion. It's Not You, It's My Enemies is when the hero decides to cut a relationship short to avoid this.
This is a Death Trope. Spoilers Ahoy!
- Yamagata in AKIRA, who is killed by Tetsuo in the full throes of psychic megalomania, and which serves to get Kaneda good and mad at him.
- Krillin in Dragon Ball and both of its extensions the hero's best friend and his son's close friend, who also has the misfortune of living in a universe where Death Is Cheap, and thus is killed anywhere from five to seven times, depending on what all you consider to be canon:
- He was killed by Tambourine, a henchman of Piccolo Daimaou, when Dragon Ball was first becoming something other than slapstick comedy, thus motivating the plot action until the end of the arc.
- He was blown up by Big Bad Freeza, an act which gave Goku the Heroic Resolve that depopulating entire planets hadn't, and finally allowed him to go Super Saiyan.
- He was turned into stone by The Dragon, Dabura, during the Buu arc, basically killing him. He got revived after Dabura died.
- He committed a Heroic Sacrifice when yet another Big Bad, Buu, was destroying the Earth - it didn't work, and all of humanity had to be brought back after Gohan avenged his death.
- Then, in the second Oddly Named Sequel, he was killed by his wife's brother. Yeah - Krillin gets killed by the personal nemeses of three more powerful loved ones.
- In the Bad Future, Krillin was one of the first to be killed.
- ... And the Distant Finale featuring Goku's granddaughter and great-great-grandson pretty much confirms he eventually dies of old age. One can only assume that a future OAV will focus on Goku powering up and destroying death in response.
- Android Sixteen is also subject to this in a subverted manner, as he originally appears to be a Friendly Enemy, later has a HeelFace Turn by attempting to destroy Cell, and ultimately becomes a Friendly Target when Cell destroys him at his leisure, prompting Son Gohan's Super Saiyajin 2 Transformation.
- Kuwabara fakes one of these against Toguro in YuYu Hakusho to get Yusuke mad.
- Later it features an inversion, followed by two subversions. Yusuke, the main character plans to pull this to activate the heroic resolve in his side kicks, so that they can finish off Sensui. The first subversion comes in the fact that even with this power up, it doesn't really help them much. The second is that Yusuke gets better.
- Usopp of One Piece hasn't died (yet), but he does get pretty damn close to it on several occasions. And he shares the same voice actor as Krillin after Funimation began dubbing.
- Lately, Hachi has been getting this. First, he gets kidnapped while trying to rescue Camie. Then, he was shot by a World Noble. During the Time Skip, he was getting beaten up by several people trying to get Thousand Sunny. And recently, when he tried to dissuade Hodi from destroying Fishman Island and overthrowing King Neptune, Van Der Decken impaled him with a hail of arrows.
- Maes Hughes, Roy Mustang's friend from Fullmetal Alchemist.
- Nicol and Tolle for Athrun and Kira, respectively, in Mobile Suit Gundam SEED.
- Is the entire point of the Identity Crisis arc of the JLA, which features a mysterious character attacking those close to superheroes, who is ultimately revealed to be intentionally invoking this trope so that all heroes will spend more time with their loved ones. It spoils some without spoiling all!
- Inverted by John Constantine in Hellblazer. His most dangerous enemies are from out of town, or from another world entirely. Someone who's reaching godlike levels of power will still give up if you put a gun to their mother's head. Also played straight; being a friend of Constantine's is basically a death sentence.
- In Origin Story, Alex Harris's girlfriend Louise, along with Nico Minoru of The Runaways (who is trying to help the two women get back home) are targeted by Bullseye when the Thunderbolts attack because a) they're helping Alex, b) they're softer targets than Alex, and c) because they're there and Bullseye just likes killing people.
- Biggs in Star Wars Episode IV. He basically existed to die; Expanded Universe materials do flesh him out further, though.
- From the Dungeons & Dragons movie, Snails dies the heroic death when facing off against the Big Bad. Considering what kind of movie this was, his death surprised absolutely no one except the characters on screen.
- In Star Trek II: The Wrath of Khan, Spock dies saving the Enterprise and her crew. (He gets better.)
- Many, many of James Bond's allies end up dying to further the plot. To list:
- Dr. No: Quarrel
- From Russia with Love: Ali Kerim Bey
- Goldfinger: Both Jill and Tilly Masterson
- Thunderball: Paula Caplan
- You Only Live Twice: Aki. Ally and Bond Girl, and actually got married to him? No way the girl was going to get to the end of the film alive.
- On Her Majesty's Secret Service: Shaun Campbell, Tracy Draco (the latter being not only an ally and a Bond Girl, and not only getting married to him, but is stated to be one of Bond's few True Loves.)
- The Man with the Golden Gun: Andrea Anders
- Moonraker: Corinne Dufour
- For Your Eyes Only: Luigi Ferrara
- Octopussy: Vijay Amritaj
- A View to a Kill: Sir Godfrey Tibbett, Chuck Lee
- The Living Daylights: Saunders
- Licence to Kill: Sharkey
- GoldenEye: Alec Trevelyan... Or is he?
- Tomorrow Never Dies: Paris Carver
- The World Is Not Enough: Valentin Zukovsky
- Quantum of Solace: Strawberry Fields, René Mathis
- Skyfall: Judi Dench's M
- A continuing trope of the Dirty Harry movies — his partners always end up dead or seriously injured. Even Harry warns them of this. One of them does make it, though... because he was smart enough to take Harry's advice to heart, and wear a bulletproof vest.
- Parodied in Last Action Hero when, in the movie-within-the-movie, they kill the hero's favorite second cousin. After four or five sequels, he was just running out of significant family members...
- Two of Constantine's friends, Father Hennessy and Beeman, are murdered to prevent them from helping him in his investigation.
- His young sidekick, Chas, dies in the final battle. This tendency to get his friends killed is one of the few things the movie's John 'Cons-tan-teen' has with his inspiration, comic character John Cons-tan-tie-n. Amusingly, the original Chas, a cockney cabdriver, is notable for his longevity after becoming friends with John.
- Mason Ashford from Vampire Academy. Rose's closest male friend and a target for Strigoi in-universe in Frostbite. Unsurprisingly he is the first real casualty among her circle of friends.
- In 24, Kim's best friend dies partway through the first season. Saddening, yes... it could have been Kim!
- In fact, 24 is full of these. Most notably, Jack Bauer's pregnant wife Teri gets killed at the end of Season One. Season five even did this twice in its first episode.
- Buffy the Vampire Slayer: despite most of the Scoobies fitting the archetype, only Tara ever really fulfilled her destiny and died of it. Willow, her girlfriend, didn't exactly get "heroic" resolve, though.
- Spartacus: Blood and Sand: Sura, Spartacus' wife, is killed because she would remind him about his previous free life. Varro, his best friend, is then targeted by Illythia and killed for the sole reason to make him suffer.
- An April 2012 episode of Castle has the writer out on a case with another cop. Both the cop and Beckett's team warn him that 3 of his partners died because of the cop's actions/attitude/craziness.
- The X-Files: Samantha Mulder. William Mulder. Melissa Scully. Deep Throat. Mr. X. The Well-Manicured Man. Diana Fowley. Cassandra Spender. It turns out Samantha Mulder, who was believed to be dead, was already dead.
- In the game Hong Kong Action Theatre!, one of the Signature Moves you can pick for your character is "Sacrificial Buddy." The films of a character with this signature always have an Extra who is a friend or relative of the role that the character plays, who is doomed to die at some point in the movie. The character must play one scene with the Extra to establish the relationship, and after the Buddy dies (usually at the hands of the Big Bad or his Dragon), the character can either completely replenish his Chi pool or get a +5 to hit whoever killed the Buddy for the rest of the movie. This is known as the "You killed my (insert relationship here), Prepare to Die" motivation.
- In the Victorian Melodrama inspired "Victorian Villainy" supplement for Forgotten Futures, it is noted that when a villain hates someone, they will always attempt to destroy the person's career, family, fortune, etc. before making any direct attacks upon the object of their hatred, with the typical mentality being "I want them to suffer first!" This is one of several reasons why it's often safer to be a hero than a hero's friend.
- Due to the magic of Relationship Values, you get to choose who gets to be this in Mana Khemia: Alchemists of Al-Revis. Isn't that great. No worries, they do get better, because it'd be downright cruel to kill off the character you spent most of the game getting to like you and probably have an attachment to at this point.
- Exit Fate has a variation. Every playable character (there are 75 of them) has up to three "relationships" with other characters (becomes available when they become playable) classified as A (significant friend or love), B (close friend), C (respected ally) and F (hates the person!). If (assuming both are in the party) the second person is knocked out, the first gets a boost. For example, if Vanrushal (a vampire) goes down, Luther (an exorcist) gets an uplifting morale boost from seeing his hated enemy go down. If Daniel is knocked out, Ayara is spurred to take revenge. Of course, being knocked out is only temporary unless the whole party is defeated.
- In Mass Effect 2, Thane Krios' wife was killed by the associates of one of his targets as revenge. Being the best assassin in the galaxy, Thane was very effective at tracking them down and exacting vengeance.
- Dragon Age II is one hell of a bad time if your name is Hawke. One sibling dies less than ten minutes into the introduction; the other one is killed, enlisted by the Grey Wardens, or forced into the mage/templar conflict; and the matriarch of the family becomes the target of a serial killer that commits gruesome Body Horror on her. It's a wonder that Player Character Hawke doesn't completely break down by the end of the game.
- Isara Gunther in Valkyria Chronicles is the hero's adopted and beloved sister, his tank driver, and a skilled tinkerer who constantly provides the keys to winning key battles. Her death ends up bringing the squad together just when the battles and the stakes are pushed through the roof. And that doesn't even account for the effect it has on both Welkin AND Rosie.
- Jackie Ma of Sleeping Dogs is impossible to dislike. He is Wei Shen's connection to his childhood along with much of the comic relief of the game, and also looked to be trying to turn his life around toward the end. So of course, they couldn't let him live.
- Kid Radd plays this toward the end, where Bogey forces Radd to kill him, so that Radd can get the power-up inside his body.