Sometimes, a character you care for is going to die. Rather than killed off by the bad guys or some cosmic whim, though, the murderer is another character who cares very much for the deceased. Perhaps your little sis has become a Tragic Monster and needs to be staked, or maybe you have to Fight Your Friend to the death. Occasionally it's a case of Shoot the Dog or Mercy Kill. In any case, the characters know each other, as well as their relationship to each other. And the killer knows that the other has to die for anything to be resolved. In some cases leads to Cradling Your Kill.
In video games, this is invariably a Player Punch. This trope usually doesn't villainize the killer, since the now-dead character generally has to be killed to right wrongs, or at least keep the story going. Doesn't stop him or her from feeling like crap afterwards, though.
As a Death Trope, ALL Spoilers will be unmarked ahead. Beware.
- In an early crossover between Batman and Deadman, the latter ends up possessing a criminal and going on a couple of dates with his girlfriend to keep his cover. Unfortunately, having gone years without human affection, Deadman eventually falls for the girl and abandons Batman's operation in hopes that he can convince her to go straight. Problem is, she finds out he was working with the cops and she tries to kill him and Bruce, forcing Deadman to pull the trigger on her. Angsting ensues.
- In For the Man Who Has Everything, Superman has to do this to escape the Black Mercy. In accepting that his wonderful new life is a dream, he causes the dream Krypton to explode just like the real one. Similarly, Batman has to let Joe Chill kill Thomas and Martha Wayne in his dream just as Chill did in life to escape the Mercy.
- In the House and Powers of X setting, X-Men can resurrect mutants so easily that it is common to kill one of them to cure him. When possible, those in need of death and resurrection ask as a favour to be killed by those they respect or love most. Most striking "love" example is Magneto killing Scarlett Witch, triggering X-Men: The Trial of Magneto.
- Psylocke had to do this in Uncanny X-Force. Twice. The first was her lover, Archangel; he was possessed by Apocalypse, forcing her to completely erase his mind (resulting in a Death of Personality for Warren). The second was her brother, Jamie; his future self was a multiverse-conquering demon, so she killed him to save the worlds.
- Avengers: Infinity War:
- The only way to obtain the Soul Stone is to kill someone you love the most. Thus, Thanos killed his adopted daughter Gamora, the one who he loved the most. Ironically, this is also why the universe seems to have bestowed the role of the Soul Stone's guardian onto the Red Skull. Unlike Thanos, he's genuinely heartless, so while he's more than willing to make the sacrifice, he can't, because he has no loved ones to sacrifice.
- On two occasions in the same film, heroes attempt to do this to keep the stones out of Thanos's hands — Gamora tells Star-Lord to kill her if she's captured to keep Thanos from extracting the location of the Soul Stone from her, and while the Avengers attempt to remove the Mind Stone from Vision safely so it can be destroyed without killing him, eventually Wanda is forced to try and destroy it while it's still in his head when they run out of time. Thanos prevents the first by using the Reality Stone to turn Peter's gun into a bubble blaster when he pulls the trigger on Gamora, and undoes the second by using the Time Stone to undo Vision's destruction. Nonetheless, Thanos expresses his admiration for both of them for being willing to go so far to try to thwart him.
- In Avengers: Endgame, Black Widow and her best friend Hawkeye are sent to retrieve the Soul Stone. When they learn of the sacrifice that must be made, neither one of them is willing to kill the other to get the Stone. However, they're both perfectly willing to kill themselves so the other person can have the Stone, leading to a bizarre "fight" between the two where they both try to fling themselves off the cliff while trying to stop the other from doing so. Black Widow ends up the "winner" of the fight, which gives Hawkeye the Stone.
- Towards the end of Deewaar, police officer Ravi shoots his criminal brother Vijay, who dies of his injuries not long after.
- In the kung fu-period piece film, The Emperor and His Brother, the elderly chief of the Red Lotus Clan is forced to kill his 12-year-old son in order to preserve family honour, due to the boy unintentionally giving away the La Résistance hideout to the Manchurian invaders and causing the family to be arrested.
- Will Smith's dog in I Am Legend.
- I Shot Jesse James: Robert Ford, one of the closest friends of Jesse James, is the one that kills Jesse himself. The love part of the trope becomes clear at the end of the film during Bob's Dying Declaration of Love towards Jesse.
- For as much as the James Bond franchise has the title character kill so many people and bed so many women, there's been one instance where he's killed someone he loved — Elektra King in The World Is Not Enough, who turns out to be that film's Big Bad mastermind.
- Double Subverted in Kill Bill. At first, all we see of The Bride is her Roaring Rampage of Revenge against Bill, her ex-lover, but after she kills him, she breaks down sobbing for several moments.
- In John Woo's The Killer, the title character has to put a bullet to Sidney Fung, his best friend, in an I Cannot Self-Terminate moment, after he went through serious hell to get the money the Killer needs to have Jenny's eyes fixed to him and got shot by the bad guys.
- In the director's cut of Kingdom of Heaven, Sibylla learns that her young son has leprosy, just weeks after her brother succumbed to the same illness. Having witnessed firsthand the horrible suffering her brother endured as the disease ravaged him, Sibylla refuses to subject her son to that, and, having no other way to prevent it, poisons him to give him a quick and painless death.
- The ending to Million Dollar Baby. The film's star boxer has suffered a career-ending injury, is paralyzed below the neck, has no hope of recovery beyond being immobile for the rest of her life, and because she is no longer able to pursue her dream of being a boxer, she wants to die, but cannot kill herself due to her injuries. Her manager, who has during the course of the movie becomes like a father to her, later makes the painful decision to cut off her life support and give her a massive dose of tranquilizers to avert her prolonged suffering.
- Monsieur Verdoux: Implied. There is something in the way Charlie Chaplin (as the titular anti-hero) delivers his vague statement about losing his wife and child to a "happier place" (ie. Heaven), after losing everything in a stock market crash, that hints that he may have, shall we say, given them a "helping hand".
- Both the film and book version of Of Mice and Men show two examples. The first is a subversion depicting a man who has to have someone shoot his rabies-infected dog. He laments that he didn't do it himself. It is later invoked when George has to kill Lenny to save him from an angry mob.
- As mentioned in the Literature section, Old Yeller is one of the oldest examples in film. At first, there is a Hope Spot tease when Travis pens the dog in a corncrib, hoping he won't turn rabid — he does.
- Subverted in the ending of Pan's Labyrinth, when Ofelia has to kill her baby brother to prove herself as a princess of another world (the Faun claims he just needs to draw a few drops of blood and that her brother will suffer no lasting harm, but she doesn't believe him). She refuses to do so. Turns out it was a Secret Test of Character; by refusing to take her brother's life she proved herself worthy of returning.
- In Pixels, the confrontation between Ludlow and Lady Lisa has shades of this, with Ludlow unable to bring himself to kill the love of his entire life.
- Ransom. Corrupt cop Jimmy Shaker seems to care for Maris, his girlfriend and fellow kidnapper. When he kills the two expendable remaining kidnappers to make himself out as a hero cop, she shoots him in turn, clearly expecting him to dispose of her as well. He seems a bit shocked at this before he kills her as well with apparent remorse.
- Averted in Serenity: "bullet in the brainpan squish." Just enough to scare the audience into thinking that was the planned ending. It is easy to imagine the writer pulling that one.
- Shaun of the Dead: Shaun shoots the zombie Barbara after her transformation.
- In Tinker, Tailor, Soldier, Spy, Jim Prideaux and Bill Haydon are known as "The Inseparables", their relationship so close that it's possibly not totally platonic. But when it turns out Haydon is The Mole, Prideaux is the one who executes him.
- Universal Soldier: The Return: Luc Devereaux had a partner named Maggie, who spend most of the time protecting Luc's daughter Hilary from ruthless Uni Sols (led by the evil S.E.T.H.). However, Maggie gets killed by S.E.T.H.'s right-hand man Romeo, who takes her body back to the Uni Sol building, where a neural implant is placed inside her brain to revive her as a Uni Sol to serve S.E.T.H., much to Luc's grief. Even when an angry Luc manages to destroy S.E.T.H. and free Maggie from the evil programming, Maggie stated that she won't spend the rest of her life as a killing machine and that Romeo will be leading the remaining Uni Sols into war in revenge for S.E.T.H.'s demise. As a final request, Maggie asked Luc to blow up the building with herself and the remaining Uni Sols inside, and Luc reluctantly obliges, knowing that Maggie was a close friend who risked her life protecting Hilary.
- The Usual Suspects has a sickening version. According to a legend, when Keyser Söze was a small-time gangster, someone once tried to take him down by going after his wife and children. He came home to find them being held hostage, guns and knives being held to them, pleading eyes, etc. Not to be cowed, he killed them all himself, then the shocked hostage-takers, "then their parents, then their parents' friends..."
- In The Wolfman (2010), the first werewolf kills his wife and son; Lawrence kills his father and almost kills Gwen too.
- X-Men: The Last Stand:
- Jean Grey as the Phoenix kills both Professor X and Scott Summers.
- Wolverine is forced to kill Jean to stop her murderous Phoenix alter-ego from destroying everything.
- First invoked, then cleverly subverted in Zombieland. Wichita asks Tallahassee and Columbus to perform a Mercy Kill on her infected sister, Little Rock, then stops them and insists that she be the one to do the deed. She then promptly turns the gun on the two men so that she and her NOT-infected sister can steal their weapons and vehicle.
- The Decemberists' Culling of the Fold is, basically, about this. For pretty much no reason. Just because someone's got to do the culling of the fold.
- Played with in Ga1ahad and Scientific Witchery by Mili, which is about a knight on a mission to kill the witch who created/reanimated him, and whom he had a past romantic relationship with. They seem to reconcile in the end, though...
- Judas in the musical Jesus Christ Superstar (the Biblical text itself could be the basis for this trope too, depending on how you look at it).
I don't believe he knows I acted for our good
I'd save him all the suffering if I could
- Othello is led by the lies of Manipulative Bastard Iago to do this to his wife Desdemona.
- In Richard Wagner's "Ring", Wotan does this to his son Siegmund in Die Walküre and Brünhild to Siegfried in Götterdämmerung, although the actual killing is done by Hunding in the first case, and by Hagen in the second.
- In Twelfth Night, Orsino all but names this trope in the final scene, when he believes "Cesario" to have betrayed him:
Orsino: Why should I not, had I the heart to do it, Like to the Egyptian thief at point of death, Kill what I love?
- Full Metal Daemon Muramasa:
- This trope forms one of the most important pillars for the story as the main character Kageaki has to deal with a curse known as The Law of Balance which stipulates that for every one slain in hatred, he must also slay a loved one. A friend for each foe. A big part of the story is centered around him trying to work around this and finding different answers. And the real tragedy of this all is that isn't even a curse. Rather it is something that is meant as a very harsh lesson to divert humanity from their own self righteousness. The idea is that for every one you kill you deem evil, you are also killing someone else's good, and thus the curse is meant to steer people away from black and white thinking. Of course, things went horribly, horribly wrong, leading to one of the bloodiest conflicts in history and the prayer for peace became known as a curse.
- It is also shown that the curse is not flawless. The Big Bad Hikaru is also under The Law of Balance, however she is able to kill freely without having to act in response. All this is due to her submitting to an Above Good and Evil mindset, she doesn't hate anyone and thus doesn't have to slay in love. This is however also why she couldn't kill her mother Subaru as she was the only person in the world that Hikaru genuinely hated.
- This curse also ties into the Relationship Values aspect of the VN. Only the twist is that whoever has the highest value is the one that Kageaki has to kill during a key point in the story.
- The trope also comes into play in various ways during the conclusion of each route:
- At the end of the Hero route he ends up having to face down with Ichijo in a duel to the death as not only is the Law of Balance now live due to a prior kill, but also cause of their own personal views and philosophies being thoroughly incompatible despite their burgeoning love for each other.
- In the Nemesis route, Kageaki is now facing down with the silver knight that killed his father, determined to get his revenge and then face punishment for his crimes. In a bit of Dramatic Irony, he doesn't know that the knight and his fathers killer is in fact Kanae, the very woman who he has grown to love and the one who promised to bring him judgement and is in her own way fulling that promise, even if it means their mutual demise.
- During the climax of the Conquerer route, Kageaki invokes this curse intentionally by killing the one he hates most of all. The twist is that the one he killed was himself, and the one he loves most of all is the Big Bad herself, Hikaru, his own daughter that he had sworn to protect. With this, even the huge gap in power becomes irrelevant as the curse demands that its due is paid. This also served Hikaru herself as this act served as an absolute confirmation that her father did in fact love her.
- Frequently occurs in Higurashi: When They Cry as the main characters are True Companions yet often kill each other in different arcs. Keiichi in Onikakushi-hen might be the truest to this trope. He killed Mion and Rena in self-defense, crying while doing so. The series implies he's in love with one of them, though which one depends on the arc (Onikakushi itself suggests Keiichi loved Rena). In an even more depressing twist, in reality, they were of no harm and he was simply insane and thought they were trying to kill him.
- Fate/stay night:
- Saber's backstory. She killed her own son, Mordred. It's somewhat vague in the main Fate entries as to whether or not she loved Mordred, however, but Fate/Grand Order does suggest that she did/does.
- In Heaven's Feel "Mind of Steel" Bad End, As a result of crossing the Despair Event Horizon, Shirou follows Kiritsugu's path. As a result, he allows Rin to put down Sakura and intends to kill anyone else that stands in his way of being a hero, including Rin (who is predicted to go mad with grief and attempt to win the war so she can wish for Sakura's resurrection) and Illya.
- In Heaven's Feel, Rin and Sakura attempt to kill each other. Near the end, Rin attempts to charge at Sakura with a blade, but falters, get severely wounded by Sakura as a result, and admits to Sakura that she does love her.
- After learning his mistake in not Mercy Killing Shirley when she asked him to after she turned into a Dead Apostle, it leads to Kiritsugu becoming more willing to use this trope, but he's not happy about it. It leads to him killing his father to prevent him from continuing similar experiments, blowing up a plane with Natalia onboard to prevent another outbreak if it were to land, and killing illusions of Irisviel and Illya to reject the Holy Grail.
- Kariya attempts to strangle Aoi to death after she gives a "The Reason You Suck" Speech when she's tricked into thinking he's the one who killed Tokiomi. She becomes brain-damaged enough that she's left wheelchair-ridden and has to be taken care of by Rin until her eventual death from complications a few years later.
- Kirei, a sadist who doesn't want to be a sadist, is horrified when he realizes that he's jealous that he didn't get to kill his wife and his father. He doesn't necessarily love them, though, at least not in the normal sense and/or he really wanted to.
- Fate/stay night:
- hololive: During a playthrough of A Way Out, as expected for those familiar with the ending of the game, Calliope and Kiara's characters are pitted against each other in a fight to the death and the two of them act it out as if it were themselves, later proving to be actually much more than that on Kiara's part, making the situation that much more heartbreaking. Though Calliope's romantic interest in Kiara is dubious, it still hits hard hearing both of them crack.
- In the Season 8 finale of Adventure Time, Finn accidentally kills his grass duplicate Fern after Fern attempted to trap Finn in a dungeon and take over his life not long after he confessed to Fern that he saw him as a brother.
- American Dad!: When Stan attempts to "toughen up" Steve and his friends by teaching them to herd cattle as cowboys, he has them bond with the cows, then forces them to personally slaughter one with their bare hands. He claims it's because "real men kill the things they love before they can be used against them".
- In the fourth season finale of Archer, Sterling, Lana, Ray, and Cyril are all trapped in an underwater base and have to make a long swim to safety, and there are only three wetsuits. To save the rest of the team, Archer offers to let one of the others drown him, with the expectation that once they reach the escape vehicle, they can revive him. Lana does the honors and finds it a lot harder than she expected.
- In Danny Phantom's Made-for-TV Movie The Ultimate Enemy, Danny has grown up to be an Omnicidal Maniac, and upon meeting his past self and upon seeing his existence is in jeopardy, goes back in time to set in motion the events that led to his current state: The death of everyone he loves. He's darn happy about it, too.
- Star vs. the Forces of Evil: In the Season 3 finale, when everyone else has fallen to the insane Meteora, her mother Eclipsa takes up the wand to fight her. She is forced to (seemingly) kill her, and then falls to her knees, sobbing.
Star: ...what did you do?
Eclipsa: What I had to.
- In the Grand Finale of Star Wars: The Clone Wars, Order 66 is initiated and Ahsoka and Rex find themselves fighting Jesse and the rest of the 332nd Legion to survive. They try everything they can to avoid killing them, but fail; Rex is forced to gun down several troopers to save Ahsoka, and Darth Maul's actions during their escape cause the ship to crash land, killing Jesse and everyone else onboard. The second-to-last scene of the series is Ahsoka and Rex giving the Legion a funeral in the ruins of their ship before going into hiding as the Empire rises around them.
- On the other side, it's shown that the clones of the 332nd Legion all universally adore Ahsoka, even painting their helmets to resemble her face as soon as they heard she was coming back, showing that they don't care if she's no longer technically a commander, they still respect her unconditionally. The brainwashing from their chips gives them no choice but to attempt to execute her when Order 66 is given, and it's made clear from Rex that they are all aware of what they're being forced to do, but completely unable to stop themselves from acting on it. Before Rex's chip is removed, he fights it as long as possible, shedding tears while trying to warn her, before he eventually pulls the triggers.
- Saddam Hussein would order his bodyguards to kill members of their family, so they would "have nowhere to run."
- In seppuku, the role of the kaishaku is to behead the man who has just committed the act. It was usually filled by a friend or at least a loyal servant. This likely formed because seppuku, being a suicide ritual in which you stab yourself in the abdomen and cut left from right, would otherwise bring about an incredibly painful end. The exact time to behead varied and was discussed between the principal and kaishaku beforehand - while initially the beheading was performed after stabbing themselves and cutting horizontally, it changed as time went on to that they may be beheaded as soon as they stab themselves before they can even show pain from it, or even just showing they intended to go through with it by making a motion toward grabbing the suicide blade.
- This is the (incredibly twisted) logic when it comes to some cases of Pater Familicide (or any variant thereof), where the killer does so because they firmly believe that their family is better off dead.
- Nazi Propaganda minister Joseph Goebbels and his wife Magda committed suicide in 1945 because it was clear that the war was lost. Before doing so, they made all their six children swallow cyanide pills so they could die too.
- Japanese criminal Sade Abe strangled the man she loved to death while having sex. Afterwards, she cut off his penis and carried it with her. Her morbid lust story later inspired the film In the Realm of the Senses (1976).
- Obsessive stalkers can also cross into this territory.
- John Lennon was presumably shot by a man who claimed to be his biggest fan.
- The "merciful death" version of this is the reason many people have elderly or terminally ill pets put to sleep, and is a major driver behind the "death with dignity" movement, which fights for terminally ill people's right to die on their own terms.