History Main / MercyKillArrangement

* ''Anime/FullmetalAlchemist'': Colonel Roy Mustang aims to be a good leader for the country of Amestris. He asks his trusted subordinate Riza Hawkeye to kill him if he ever "goes too far", as he fears that his ambitions might lead him to do too many unsavory things.

* Near the end of ''[[VideoGame/CastlevaniaChroniclesOfSorrow Castlevania: Aria of Sorrow]]'', [[TheHero Soma]] asks this of [[RetiredBadass Julius Belmont]], in the event that [[spoiler:Soma, who is Dracula's reincarnation, fully becomes Dracula]]. The Bad Ending of ''Aria'' and its sequel ''Dawn of Sorrow'' both show Julius making good on his promise.

* In ''Literature/{{Dracula}}'', after Mina is bitten by Dracula, dooming her to become a vampire if she dies while Dracula still lives, she makes her friends and husband promise to [[StakingTheLovedOnes stake her]] if she turns.

* ''LightNovel/HowARealistHeroRebuiltTheKingdom'': After making a number of ShootTheDog moves to win the CivilWar in Elfrieden and then defeat Amidonia, Souma becomes so worried about potentially JumpingOffTheSlipperySlope in dealing with his political enemies that he secretly orders Carla, who is enslaved as a palace maid in lieu of a death sentence for treason, to kill him as a last resort should his rule turn tyrannical--a move that, due to the enchantments on her SlaveCollar, [[MutualKill would also mean her own immediate death]].

* In the fifth book of ''The Helmsman'' series, the protagonist is stranded on an enemy planet with three other men, one of whom is the Emperor. The Emperor cannot afford being taken captive, so he makes the other three swear they'll shoot him first.

* ''LightNovel/ReignOfTheSevenSpellblades'': Nanao fears that [[LoveHurts her warring desires]] to both pursue a romance with Oliver and fight a DuelToTheDeath with him could drive her to madness, and asks Katie to kill her if that ever happens. Katie doesn't reply.

* ''Literature/ReignOfTheSevenSpellblades'': Nanao fears that [[LoveHurts her warring desires]] to both pursue a romance with Oliver and fight a DuelToTheDeath with him could drive her to madness, and asks Katie to kill her if that ever happens. Katie doesn't reply.

* Dekka in ''Literature/{{Gone}}'', fearing that she is infected by the parasitic bugs that she was trying to kill, makes Sam promise to kill her if it comes to that. [[spoiler: Sam breaks his promise, keeping her alive to do "surgery" on her - physically tearing the bugs out of her body and then having [[HealingHands Lana]] heal the resulting wound.]]

-> ''“He was willing to kill me. And I’ll always be grateful.”''

* In VideoGame/SuikodenV: [[spoiler:Ferid orders Georg to kill Arshtat in case she becomes insane by the power of the Sun Rune.]]

* ''Film/AvengersInfinityWar'': Gamora has Star-Lord promise to kill her if Thanos ever captures her. When Thanos does grab her, [[spoiler:Star-Lord tries to keep his promise without wasting a second, but Thanos stops him using the Reality stone.]]

* ''Anime/FullmetalAlchemist'': Colonel Roy Mustang aims to be a good leader for the country of Amestris. He asks his trusted subordinate Riza Hawkeye to kill him if he ever "goes too far", as he fears that his ambitions might lead him to do too much unsavory things.

* ''VideoGame/HonkaiImpact3rd'': In one of the supplementary comics, it's explained that Valkyries who fight in the frontline against the forces of Honkai will always be under the threat of getting Honkai corruption and turn into a mindless, murderous zombie. It's a common arrangement that, if a Valkyrie ends up getting corrupted by the Honkai, their friend would have to kill them on the spot.

* In the backstory for ''VideoGame/FireEmblemPathOfRadiance'', Greil became a killing {{berserker}} while under the influence of Lehran's Medallion. His wife Elena managed to take the medallion away from him, but took a fatal blow when Greil ran his sword into her. Horrified at what he did, Greil crippled his sword arm and hired the assassin Volke for various things, one of which is to be Greil's killer if the former ever went berserk again. Of course, that never came to be, as Greil was killed by the Black Knight. Volke kept his arrangement with Greil a secret, only telling Greil's son Ike when the latter proved mature enough to know.

* In the ending of ''Videogame/MegamanX4'', after seeing the chaos caused by Repliforce's coup and how easily [[BigBad Sigma]] was able to trick them into becoming his pawns, Megaman X asks his friend Zero to destroy him if he ever shows signs of going Maverick.

* In ''Videogame/NeverwinterNights2: Mask of the Betrayer'', your character is afflicted with a curse called the Spirit Eater, which [[HorrorHunger requires them to feed on the spirits of others and eventually drives everyone who suffers from it insane]]. If you recruit Okku the Bear God as an ally, you can [[RelationshipValues gain influence with him]] by giving him permission to rip out your throat if you ever lose control of the curse, and he promises to do so, and to not take any enjoyment from it.

* ''Film/VanHelsing'': The title character has been bitten by a werewolf and [[FangsVersusFur must use the supernatural strength bestowed by the transformation to kill Dracula]] before the twelfth stroke of Midnight. While Van Helsing deals with Dracula, he sends Anna and Carl to search Dracula's castle for a cure for lycanthropy, and gives Carl a silver stake, insisting that Carl must destroy him if they fail to administer the cure before the transformation becomes permanent.

* ''Film/VanHelsing'': The title character has been bitten by a werewolf and [[FurVersusFangs must use the supernatural strength bestowed by the transformation to kill Dracula]] before the twelfth stroke of Midnight. While Van Helsing deals with Dracula, he sends Anna and Carl to search Dracula's castle for a cure for lycanthropy, and gives Carl a silver stake, insisting that Carl must destroy him if they fail to administer the cure before the transformation becomes permanent.

* ''Film/VanHelsing'': The title character has been bitten by a werewolf and must use the supernatural strength bestowed by the transformation to kill Dracula before the twelfth stroke of Midnight. While Van Helsing deals with Dracula, he sends Anna and Carl to search Dracula's castle for a cure for lycanthropy, and gives Carl a silver stake, insisting that Carl must destroy him if they fail to administer the cure before the transformation becomes permanent.

* In ''Manga/SchoolLive'', Yuuri promised Kurumi that if she became a ZombieInfectee that Yuuri would be the one to kill her before she turned. [[spoiler:Early in the manga (and late in the anime), Yuuri becomes dangerously close to having to kill Kurumi as she slowly subcomes to a zombie bite. Thankfully, Miki arrives with an experimental vaccine that saves Kurumi... [[YourDaysAreNumbered for the time being]].]]

* ''Film/AvengersInfinityWar'': Gamora has Star-Lord promise to kill her if Thanos ever captures her. [[spoiler:Star-Lord tries to keep his promise, but Thanos stops him.]]

* In ''VideoGame/DivinityOriginalSinII'' when you recruit Lohse after Act 1 she makes one with the player, since her DemonicPossession problem is only getting worse.

* At the end of the ''Literature/{{Discworld}}'' novel ''Discworld/TheFifthElephant'' this is {{Implied|Trope}}. Angua (a werewolf) asks her boyfriend Carrot if he would kill her if she went off the rails the same way her brother did (having gone into a half crazed state after his EvilPlan was thwarted). Carrot answers [[LawfulGood "Yes"]], which was exactly what she wanted to hear.

* Dumbledore in ''Literature/HarryPotter'' secretly arranges a mercy kill for himself with [[spoiler:Severus Snape]] when he learns that Lord Voldemort has set Draco Malfoy the task of killing him. He's dying anyway as a result of mishandling a cursed artifact, but doesn't want the boy's soul to be tainted by murder, and is afraid of a much less dignified death in the event that one of the more sadistic Death Eaters gets to him first. [[spoiler:In addition, he had hoped that the arrangement would break the power of the Elder Wand, its last owner dying undefeated]].

[[folder: Theater]]

A sub-trope of ThePromise and ThanatosGambit. A super-trope to KryptoniteRing, when a character entrusts a special weapon to an ally in case they bad, and SuicideByAssassin, when a character hires a contract killer as part of an assisted suicide. Compare to BetterToDieThanBeKilled, in which a character tries to commit suicide rather than face an undesirable fate. Also compare SuicidePact when individuals arrange to commit suicide together or kill each other under some circumstances. See also BetrayalInsurance, which is less about mercy and more about preventing other characters from stepping out of line.