Both instantiated and subverted in the episode "I Was Made to Love You" from season five of Buffy the Vampire Slayer, where, after chasing Robot Girl April for most of the episode with the intent of bringing her down, Buffy finally ends up staying with her as she slowly fades away, allowing April to "die" with dignity. Later, however, she does not show such concern for the worth of the "Buffy-bot" Spike has built for his amusement. Certainly, anyone would be Squicked over being the basis of somebody's -ahem- artificial stimulation, but the series had established that these robots are people too.
Buffy freaks out in "Ted" when she thinks she's killed the eponymous character in self-defense, but when he comes back and is revealed to be a robot, she has absolutely no qualms about destroying him (though he was an assholeSerial Killer).
Buffy has no problem with beating Spike to a bloody pulp shortly after voluntarily sleeping with him after his Heel-Face Turn. Well, she beat him to a bloody pulpwhile she was sleeping with him, too. Sure, Spike is a vampire (but so is Angel, Buffy's previous lover). The justification given was that Spike possessed no soul (true at that time), while Angel did.
It's clearly implied that Buffy knows this attitude is wrong, yet does it anyway. One example is when Buffy starts talking to Spike about things she won't reveal to the Scoobies. On the surface this hints at a new closeness between them, but in "Once More With Feeling" Spike says (well, sings actually) that it's only because he's a "dead man" and so her confessions don't have to count — Buffy looks away guiltily. Later on when they start having sex, Buffy feels angst not only about the things Spike is encouraging her to do, but also over how she's using Spike purely for thrills without respecting the love he feels for her, or even acknowledging that it's genuine love at all.
When Willow turns evil and kills people in season 6, Buffy tries her very best to help her and worries for her sake more than for the people she's trying to kill. When Anya turns evil in season 7, Buffy immediately decides she has to kill her, justification being Willow is human, Anya is a demon. It is explicitly said later in the episode that vengeance demons have souls, which makes it all a lot worse.
There are other incidents in Buffy which suggest that, so far as Buffy is concerned, humans are outside her jurisdiction, end of story. The only time she killed humans intentionally was in "Spiral", and the Knights of Byzantium didn't leave her with any other choice, as they were directly engaging her in armed conflict.
Actually, she also killed Caleb in the series finale.
Then again Caleb had already killed two potential slayers (Molly and Dianne), stabbed another one and gouged one of Xander's eyes. Mostly self defense
When Willow goes dark and on a Roaring Rampage of Revenge against Warren after he shoots Buffy and Tara, killing the former, Buffy is literally the only one of the Scoobies who wants Warren to face human justice for his crimes, while Xander and Dawn are so disgusted and pissed that they openly support Willow's intent to kill; after she succeeds, even Buffy reluctantly admits that Warren may have deserved to die. Nonetheless, the Scoobies all rally to defend Warren's ex-cohorts, who Willow is now targeting, because they had done nothing to deserve death.
In Season 6, there is Buffy's killing of the guy who was cursed by Anya to be tortured in a hell dimension. He had a very legitimate grievance with Anya, and he's unconscious and helpless, and he's killed like it's nothing. Also the bank-robber demon, who hasn't really done anything worthy of summary execution, yet is executed after first being knocked unconscious. Killing humans under any circumstances is apparantly an atrocity, but demons can be killed for crimes that would only warrant jail-time for a human and it's nothing.
In Angel, the rule is more like "what measure is a dangerous non-human?" Killing innocent demons is treated as a hate crime almost as bad as killing humans (see the season 3 episode That Old Gang of Mine) but killing demons who are a) animalistic and predatory or b) evil is treated as heroic, whereas killing a human is treated as wrong no matter how evil the human is.
In fact, there's a scene in the season 3 episode Forgiving where Angel is threatening to torture a human and Lorne, who's a demon, tries to dissuade him, saying "Angel, that's not a slimey demon you've got there, that's a human". Apparently, even good demons value human life more than demon life.
Actually, Angel's group seems to believe this more than Angel - when he let Darla and Drusilla kill all those lawyers, he was doing exactly what he would have done if they were demons. He doesn't see it as a Moral Event Horizon, though the group do.
However, Angel had Lorne assassinate Lindsey, and two of members of the Circle of the Black Thorn assassinated by Illyria were also human, at least in appearance. Speaking of Circle of the Black Thorn, there was also that politician that Gunn killed.
Oddly, Smallville lampshades it and tosses it aside in the 7th season finale. The sentient, apparently emotional robot Brainiac, at Clark's mercy, tells him he could never kill a man. Clark quickly replies "You're a machine," then electrifies him.
Another episode does have Clark upset after he unintentionally kills a decidedly non-human alien (and, in fact, a criminal by Kryptonian standards) in a forced arena fight. Apparently, sentient organic life merits consideration whether human or alien but sentient AI systems do not.
Russell T. Davies has a rule for his tenure in prohibiting humans from shooting other humans with "real" weapons. This rule does not, obviously, extend to Cybernised humans, the Futurekind (savage humans) or the formerly-human Toclafane. In fact, the rule gets broken in Russell T Davies' own "Tooth and Claw", in which Queen Victoria shoots a human traitor with a revolver.
Honestly, this show suffers from this trope with the Doctor himself despite the Doctor being an alien. He kills numerous non-human aliens, he does try to show mercy usually but is a bit schizophrenic about it. On the other hand, he hasn't directly killed a single human on camera.
The show is later much more consistent about this. In "The Hungry Earth"/"Cold Blood", a major conflict arises from the Doctor trying to prevent a woman who believes her child murdered from killing a captured reptilian agent, for the sake of proving that humans can in fact be civilized.
One example where the trope is played straight is in "The Impossible Planet"/"The Satan Pit". Faced with a choice between rescuing his human companion and a few others and dozens of enslaved tentacle-faced aliens, the Doctor picks the companion. Despite having a time machine.
He repents for this in "Planet of the Ood", by opting to free the aformentioned tentacle-faced aliens from slavery permanently.
The Doctor also had a long running argument with the Brigadier about "the military mind's" tendency to solve everything with "five rounds rapid". Completely averted with "Doctor Who and the Silurians"; the Doctor is upset at the Brigadier destroying the Silurian base.
The two-parter "The Rebel Flesh"/"The Almost People" explores this with the doppelgängers ("gangers" for short). Every character except the Doctor and Rory consider the gangers to not be human. The Doctor and his ganger manage to prove them wrong, and throughout the episodes the death toll for gangers and originals is pretty even, with two of the eventual survivors being gangers.
Even in the above examples, the Doctor's attitude is iffy at best. The Doctor defends the rights of a Silurian prisoner but when she gets killed anyway, he protects her human murderer (who's an attempted mass murderer) yet does nothing to prevent the death of the dead Silurian's vengeful sister, even though apart from one being green they seem to be Not So Different. He claims gangers are people, then kills one just to prove she is a ganger. (Word of God attempts to justify it by saying that ganger is non-sentient but it's still a massive Broken Aesop.)
Possibly the original series's most awkward example is the Ice Warriors. They appear in four stories. In one of them, they're treated as surprising allies. The other three (one of which was made afterwards) treat them as Always Chaotic Evil: In two, the Doctor kills several of them without a second thought, and in the other he stands by while someone else does it.
Averted in "Dinosaurs on a Spaceship". The Doctor is angry when he finds out the human Solomon murdered the Silurians, and when missiles are sent at Solomon's ship he leaves him to die. This proved slightly controversial despite Solomon being an obvious Complete Monster.
Done oddly in "Warriors of the Deep" where the Doctor gets upset at the humans killing Silurians and Sea Devils, even though the reptiles attacked first. Every story with Silurians tries to avert this.
Bizarrely inverted by the Tenth Doctor at one point: he forgives the Daleks for trying to destroy the universe in "Journey's End" and is horrified when his clone annihilates them, treating him like a monster. However he has no such pity for his own people (the humanoid Time Lords) for trying the exact same thing in "The End of Time".
Although they were all technically aliens, Power Rangers could kill "monstrous" villains but not "human" ones. In a particularly egregious case, a bunch of "monstrous" villains are killed but the few human-looking ones are turned good, with both of these outcomes resulting from the same attack.
This turns out to have been a case of Executive Meddling—the producers refused to kill the humanoid villains, even though the writers had scripted all villainous characters, "monstrous" and human alike, would be destroyed.
When he first appears, Andros, a Human Alien, cryptically says "Not everything human has to come from Earth." The meaning of this statement has been much debated in fandom, but seems to indicate that Power Rangers considers "looking human" and "being human" to be close enough.
In an earlier episode, Ecliptor (one of the monsters vaporized in this attack) explains that he (and presumably other monstrous-looking villains) are evil because they were built to be.
As Linkara pointed out, In Space also has an appearance of a monster who wants to be good. This implies that any of the previous monsters may have been good but cajoled into serving evil. (A lot of them are also created via alchemy or magic, especially the ones employed by Rita and Zedd, raising the question of just how much free will they actually have.)
More later seasons occasionally feature villains who are human—not Human Aliens or human-disguised monsters, but humans—being vaporized by the Rangers after taking on rubber suit advanced forms.
Three very telling examples: Camille of Jungle Fury survives and turns good despite not being human (She has a human form, but traits like her prehensile tongue suggest that this is not her true form). On the other hand, Zeltrax of Dino Thunder, who does not have a face, is killed destroyed, despite the fact that we are told not only that he is a human wearing cybernetic prostheses after a lab accident, we are even told his human name (It's Terrence Smith, aka Smitty). Likewise, Frax of Time Force is turned evil and ultimately dies, despite the fact that he also was once human before being forced into a robotic body.
Master Org spends most of the series looking like a human in eeevil makeup, but has a monster form when he's taken out (however, there's a moment of his human form being seen just before he's gooified once and for all.) Moltor and Flurious were near-humannote Their current monstrous forms were explicity caused by the series' main MacGuffin when they first touched it long ago. We never got a good look at their pre-monster forms' features, but they were wearing modified, reused Ninja Storm student outfits, which means to not have shown, the level of alienness couldn't be higher than Star Trek class. The backstory takes place too long ago for Earth humans to exist, but Moltor doesn't protest when Mack says "You were human once" and accuses him of throwing away his humanity for power. That's all Canon gives us. In the last two episodes, Moltor dies for real, and Flurious, though he does fight as a One-Winged Angel, is finally destroyed in his human-with-makeup-faced standard form by Mack, who was ''determined to finish him off even though he'd already been defeated." Mind you, Mack had... issues... at this point.
If the space series is any indication, where Zordon sacrificed himself to 'purge evil,' it could be more along the lines of their technology or whatever only recognizing and not destroying 'near-human' enemies. Astronema's right hand Ecliptor was an especially poignant example as he waffled between sides over his honour, yet still got vaped by Zordon anyway. Becoming cyborg reduces human quotient enough for the weapon to automatically swap from Stun to Kill settings. How this actually works is just....just something you don't even want to try and figure out.
Just look at those scenes to see this trope. Rita and Zedd - turned good. Divatox - turned good. All the monsters and robots - dust. Including Prince Sprocket, who was technically a kid, and comic relief duo Goldar and Rito. If you think about it, shouldn't robots be easier than humans to reprogram as good?
And this can not be pointed out strongly enough: Rito was Rita's brother. Unless Rita was originally a human(oid) adopted by Master Vile, ala Astronema.
Things of note: 1. We never do see what happened to Goldar and Rito, or Squatt, Baboo, Finster, or long-unseen Scorpina. 2. It has been speculated that Rita and Zedd being purged like that was a Villain's Dying Grace kind of thing, leaving them alive, memories intact, but now able to feel guilt over all the death and destruction they wrought. 3. Rita is implied to have been rotten from the beginning. 4. Divatox being spared was because of the fact she was supposed to be Dimitria's kidnapped sister. 5. With the exception of Ecliptor, the villains we see destroyed were much less popular than Rita and Zedd. Especially Elgar.
Kamen Rider in general has this to some degree. It normally varies on home morally right the hero is and how peaceful the monster is. The main Rider normally won't kill a non-human who isn't hurting anyone, but sometimes the Second Rider might not be as merciful and consider all of the species to be Always Chaotic Evil. Though to be fair, some of the non-human races are truly Always Chaotic Evil, such as the war-like Grongi, but most are depicted as having good and evil members.
Kamen Rider Kiva has Fangire who, while often evil, have been shown on various occasions to be capable of living peaceful lives without killing people, and to be able to love humans. However, Wataru generally has no qualms about killing them. Though he doesn't go out of his way to kill peaceful ones and has on occasion spared some.
Kamen Rider OOO has a particularly jarring example, in that the non-human in question is a main character. Ankh is a Greeed, and, technically speaking, not even alive. Very little regret has been shown about hurting or destroying others of his kind, and the only reason Ankh isn't lumped in with the other Greeed is that he is incapable of making Yummy and causing the kind of havoc and slaughter that the other Greeed can. However, even when Ankh regains enough power to create Yummy and hurt people, the thought of him dying is still upsetting to the main characters, and they try reasoning with him instead of flat-out fighting him as they would with the other Greeed, who they never try to reason with.
Brutally Deconstructed with the Inves in Kamen Rider Gaim. At first, the heroes have absolutely no problem with using lethal force against the creatures, believing them to be mindless beasts. Then comes the Wham Episode where Hase/Kamen Rider Kurokage is transformed into an Inves, while Micchy learns that many of the creatures are actually mutated humans, and that the first Inves Kamen Rider Gaim ever killed was actually his best friend Yuya. After Hase is brutally executed by Kamen Rider Sigurd, Kouta tearfully asks why the boy had to die, at which point Sigurd simply smiles and says that killing monsters is what Riders do.
Kamen Rider Faiz is pretty much based entirely around exploring this trope. With Orphenoch protagonists getting as much screentime as the Riders, and the second Rider's hatred of them regardless of alignment being only one of his many Jerkass qualities. It helps that the "monsters" are formerly human, and generally forced or bribed into evil.
Several "Muppet" productions have addressed this. The little-known holiday special "The Christmas Toy" takes on the Living Toys issue (we're starting to sense a pattern here). In "The Muppet Movie", one of the first humans Kermit meets wants him to be the spokes-frog for "French Fried Frog's Legs", effectively selling out his species!
In Atlantis, the Atlantis Expedition has allowed itself to perform war-crime experiments on some captured Wraith, because "if they were there when the Third Geneva Convention was signed, they would have eaten the attendees instead". This comes back to bite them, in the form of Michael.
It gets worse. The Atlantis team has yet to extend sympathy to any non-human, including those that used to be human, like Weir. They guilt her into killing herself and all the other friendly sapient Replicators with her. Their utter disregard for non-humans of any kind is reaching Designated Hero levels here.
The replicators aren't dead, they're just out cold, and it was Weir who pushed for it.
Some episodes show that the Wraith, or most of them, are not evil per se, but the laws of nature dictate that they feed on humans to survive. Those same laws dictate that humans do not calmly accept this, but instead kill Wraith to survive, ala dolphins killing sharks. It's all a matter of who wins, not good and evil, at least until the treatment to make Wraith not need to feed on humans is invented.
The Wraiths' unexplained specific requirement of humanLife Energy instead of nonsapient animals brings this far into the Fantastic Aesop territory. The species is just written to provoke this conflict.
It is briefly covered that the Wraith evolved because the Iratus bug fed on humans.
The Wraiths use this logic in regards to humans, making it clear that people are just food. They aren't out right cruel (compared to the Goa'uld). While they do have the runners and the like that is as much about finding food and enjoying the hunt. It is possible to argue that the humans to more torturing of Wraiths than vice versa, at least if you don't include the Wraiths feeding off of humans.
It turns out that the treatment isn't perfect, it tends to break Wraith technology.
The Atlantis team helped a non-human civilization's probe rebuild said civilization recently. It was kind of surprising that Sheppard was so amenable, given that the probe mentally tortured him.
There's a great conversation about this in "Be All My Sins Remember'd" when McKay and Zelenka create a human-form Replicator strictly for the purpose of using her to destroy the rest of the Replicators. Carter argues against destroying a self-aware being, but McKay argues strongly that she doesn't count as a life form. He later shows some discomfort, though, when FRAN displays excitement about being sent to her "death." Even the non-human doesn't think her life matters!
In Stargate SG-1, O'Neill got the whole freakin' galaxy in trouble by applying this trope on Humanoid Replicator "Fifth". If he'd just brought him with them when they escaped, he wouldn't have created RepliCarter, who would kill Fifth and attempt to wipe out the galaxy.
From O'Neill's perspective, Fifth's Face-Heel Turn just proves he was right not to trust him all along. But then. Jack's morality is a bit more black-and-white than the target audience's.
Jack still has more shades of grey though than any of Atlantis' cast.
Occasionally brought into question in regards to how casually the Goa'uld are thought of - sometimes when dealing with the Tok'ra and once with a trial between Skaara and the Goa'uld Klorel for who was allowed his body. Mostly, though, the trope is inverted with the Goa'uld, who think 'What Measure is a Human?'
This issue is also addressed with the Unas in a number of SG-1 episodes. They can seem quite menacing, but Daniel's learned how to communicate with them a bit and gets rather peeved when other people treat them like animals.
Also, in the SG-1 season-three episode "Urgo", the team encounters a program which was downloaded into their brains, and unintentionally results in an AI named Urgo. Who constantly pesters them. They go to Urgo's creator to have him removed, but Urgo is afraid that he will be destroyed. Sam and Daniel decide that destroying him would be akin to murder, because he is intelligent, aware of his existence, and afraid of death, and these together define him as sentient. They convince the rest of SG-1 and Urgo's creator to agree with them, so Urgo's creator downloads the AI into his own brain instead of destroying him.
SG-1's first season had it happen twice with Human Aliens: once with Teal'c in "The Enemy Within", and once with the Tollans in "Enigma". In both cases it contrasted the SGC, which believed that offworld-born humans and human offshoots should be afforded the same rights as Earthlings, and the NID, which didn't. "Enigma" features this gem:
Jack O'Neill: These people do have rights, you know. Col. Maybourne: Do they? Under what nation's jurisdiction? Daniel Jackson: How about basic human rights???
Teal'c got the shaft from the NID again in "Bane".
The 2000s Battlestar Galactica is practically built on toying with every permutation of this trope. At the beginning, humans automatically treat Cylons as machines and Cylons automatically treat humans as cattle. As the series goes on, dissenters emerge in both races. Made more confused by the fact that Cylons, despite being artificially born and having cybernetic neural properties, practically are biologically human, and several 'human' characters are Cylon sleeper agents.
Subverted in Victorious when Rex the puppet gets sucked into an incredibly powerful sucking machine, and suffers a serious injury. Everyone is as sad about this as if it were a real person. Played straight with Jade.
Jade: "Am I the only one who finds this bizarre?"
Farscape subverts the "duplicates are worthless" concept, hard, with a villain who has a machine that can create instant, perfect duplicates - such that the question of "which is the original" is, for all intents and purposes, meaningless. When Chiana is duplicated and one of them is killed, she tries very, very hard to convince herself that she's okay because it was just a clone and she's definitely the original... but she chokes up when she gives this speech. Both Johns are treated as equal, and when one of them dies, Aeryn can't even look the other in the face for a while. Also, the Expendable Alternate Universe treatment of identical opposites is thoroughly deconstructed (see that page). As for the show's and the characters' treatment of humans versus non-humans, well, the characters are various degrees of amoral and the creators love painful deaths, so it's hard to say.
This trope is explored with a twist (What measure is a non-animal?) in the episode "Bone to Be Wild":
Zhaan: I cannot condone what his people did, but for all this unparalleled flora to flourish, it may not be entirely unreasonable to- John: To murder sentient beings in order to save a few stinking plants? Zhaan: How animal-centric of you, John. John: Sorry, Zhaan. I forgot. You're a- Zhaan: I am a "stinking plant".
The Winchesters of Supernatural and their allies seem to care less and less about killing or torturing demons as the show goes on, despite demons possessing human bodies with the original occupant still in there. To be fair, they are in a very bad situation where mercy isn't always an option, they're facing hordes of demons and little time later on, and it's stated and shown that many demons put their hosts through a lot of punishment, possibily killing them even if they are expelled. This is why the human version of Meg calling Sam out on it was such an awesome moment.
Actually, one of the reasons Sam starts out using demon blood-fueled powers is because it lets him exorcise demons quickly and without endangering the host. When Ruby tries to persuade Sam to work with her, Sam orders her to vacate her current host. To placate him, she goes to a hospital and possesses the empty body of a Jane Doe who just flatlined, which Sam reluctantly accepts. The Winchester Brothers care less about hosts when Sam isn't in any position to be a Morality Pet or isn't really being The Heart. Or when the other is threatened.
In fact, no supernatural creatures are allowed to live, with the exception of the nest of vampires (led by Amber Benson (Tara), ironically) who live off animal blood. She gets a Mercy Kill later, when the dark sides of the monsters are brought out by their Mother. Even the sympathetic (or just pathetic) creatures, like shapeshifters (who were born preternaturally mutated and cast out from society and kill because of their Freudian Excuse) and werewolves (people who are bitten, black out when they turn, and have no idea that they spend the night murdering innocent people) must die. The only werewolf episode is "Heart", and it explores this trope.
Two of the three shapeshifter episodes, "Skin" and "Monster Movie", give us pieces of insight into the shapeshifters' painful existence; the first shapeshifter was an intentionally cruel rapist/murderer, but the second was incredibly lonely and a victim of society's narrow-mindedness and his own killer instincts:
Girl of the Week: Did you ever think you might be lonely because you kill people?
Shapeshifter: Or maybe I kill people because I'm lonely.
Which is a godawful excuse, but that guy was twisted. Dean actually felt sorry for him, which is a change. A similar example would be a man who was turning into a creature known as a rougarou, which feast on humans. He was born that way and the brothers tell him what is happening to see if he can fight it off and hold in his vicious nature. Then a fellow hunter's actions force him to turn into a monster and they are left with no choice.
In season six, we find out that all these supernatural creatures are created by the children of one Mother and tend toward Always Chaotic Evil, especially when she's around. In season seven, we see that it's still possible for at least one monster to choose not to give in to The Dark Side most of the time. Every time a monster or witch doesn't act evil, though, it never seems to last—resulting in the Hunters'position making more sense.
It's likely but not certain that the general attitude of Hunters toward Sam as an "abomination" for having psychic powers (from demon blood) by itself would have led most of them to hunt and kill him as Not Quite Human, but most gun for him pretty hard once they know he brought onthe Apocalypse.
On the other hand, Reapers must be kept alive. Considering they fulfill a function—harvesting those whose time has come—rather than actively killing, the distinction is understandable.
An odd example is Castiel, an angel. When he's losing his power and collapses, the Winchesters show genuine concern for him, despite disliking the other angels (although the others are trying to bring about the apocalypse).
In season seven, Sam still prefers not to kill and Dean still would rather kill than be sorry later (although considering everything that came between, it might be "again" rather than "still"), but Sam's not exactly stable enough to stay that way consistently, and Dean's still tormented enough that he can slip out of this practicality.
This trope is further discussed in season eight on several occasions. There's Benny, the vampire, who helped Dean escape from Purgatory, thus creating a conflict between the brothers regarding what to do with him, Dean obviously wanting to protect him. Later, in "Man's Best Friend With Benefits", Sam and Dean come across an old friend who has turned to witchcraft, and they must decide whether or not to give him a "free pass", as Sam calls it.
Hercules: The Legendary Journeys explores the question in an episode which reveals that most of the mythological monsters Hercules killed during the first season were, at one point, just as sentient and emotionally complex as anyone else. Though it's played for comedy at first, as Hercules learns all this from their bumbling Gentle Giant father, it comes to a dramatic head when he finds out that Hercules has killed them all: the ensuing fight's only resolved when a regretful Hercules (now realizing that he'd unfairly dismissed them as mindless monsters) convinces him that there really wasn't any other option, since Big Bad Hera had brainwashed them into becoming her evil minions.
This is exploited in the Mystery Science Theater 3000 episode Screaming Skull. Before the main film, Mike and the 'bots watch the Gumby short "Robot Rumpus", in which a bunch of housework-performing (and apparently non-sapient) robots go rampant and start destroying property. Gumby and his dad forcibly dismantle the wayward robots, and this is all presented as comedy. Crow and Tom Servo, robots themselves, are thoroughly traumatized by the proceedings.
On the other hand, Tom Servo has hundreds of duplicates of himself, and takes no issue with blowing them up at the end of the series.
A question often posed in The Sarah Connor Chronicles, especially relating to Cameron. The characters have varying degrees of belief in the value of Terminators as a whole and Cameron in particular; Derek Reese views her as a dangerous, inhuman threat, Sarah views her as a useful machine but who lacks emotions or a soul, and John views her as a close confidant, protector, and friend who he'll go to any lengths to protect, just as she would for him.
Interestingly, even Cameron herself angsts over this, paradoxically seeming to possess something like enough to a soul to be capable of being bothered by the idea of not having one.
This was brutally answered in an episode of The Twilight Zone called "The Lonely". A man who has been exiled to an asteroid for life is left with a female robot by a sympathetic captain. The man eventually falls in love with the robot. During his next visit, the captain tells him he's been pardoned and can come home, but there is no room for the robot. While the man tries to think of a way to take her with him, the captain shoots it in the face, revealing its wires and circutry. Seeing it for what it really is, the man leaves it behind.
Not so fast, The man didn't leave the robot by choice. He truly thought that the robot was sentient and harbored true love. It is left open ended if it was truly sapient or if it was just well programmed. Regardless, either he left once the illusion was broken, or he trudges off, denied what he truly wanted.
Played with in Mr. Bean. He had at least two companion cubes: his teddy bear and his car. Teddy can get decapitated and ripped apart every episode. The audience always laughs but also "Awwww"'s at close ups of the cute little toy bear, indicating that they sympathize with the toy but still feel it can be beaten up a little. His car provided a stranger example. In one episode, Bean's car was demolished. The audience apparently has a case of Mood Whiplash by laughing, showing sorrow, and then laughing again.
The more human-like mutants of the week on The X-Files tend to get the harsher treatment, being portrayed as instinctive killing machines (or animalistic predators), to be stopped by any means necessary. However, earlier in the series, this had yet to be established. Eugene Tooms (the liver-eating, hibernating, contortionist mutant from Season 1) was supposedly rehabilitated and released back into society. Similarly, Flukeman from early Season 2 was committed to a psychiatric institution for observation, despite being a radioactively created fusion of Primate and flatworm DNA. In the second case, Mulder argued that the creature did not deserve the same legal treatment that a human serial killer would, because he did not see it as human. Later episodes focused more on ordinary humans with strange gifts or victims of unusual circumstance (many of whom killed by accident) rather than the traditional "mutants." Later in the series, a brain-eating humanoid creature tried living like a human, but ultimately failed (proving Mulder's point). At least he got a sympathetic POV. Interestingly, in the episode featuring a severely inbred family as a Monster of the Week, this doesn't get brought up, implying that the monstrous Peacock Clan is more "human" than (presumably) human-derived mutants like Tooms.
The show 'Eureka'' typically puts one of the main characters in mortal peril as part of the Disaster of the Week; when Andy, the android deputy sherrif, is the one in danger, the situation is given exactly no less weight or gravitas. The show doesn't make light of things just because the character is a robot, and all the other characters are just as worried and working just as hard to fix things as if one of the humans were in danger.
Merlin has the Sidhe, a race of fairy-like creatures that Merlin has no qualms killing off in surprisingly brutal ways (he essentially blows them up with magic). Of course, he's also killed humans with very little remorse, but the Sidhe are notable in that many of them aren't even being particularly threatening at the time of death. Grunhilda in particular, a pixie who was just following orders from a Sidhe Elder, never harms anyone during the course of the episode in which she appears. Her only "crime" is being part of a plot to ensure that Princess Elena marries Prince Arthur (a plan that doesn't involve killing anyone), and she comes across as genuinely fond of her ward.
Generally averted in Grimm. Nick is fine with letting supernatural creatures live their lives, as long as they are not breaking the law and has treated them as he would to human beings in comparative situations. This comes to a shock to many Wesen as this approach was unheard of among Grimms. Many still remain wary of Nick while the ones that get to know Nick are surprised that Nick seems to ignore the traditional feuds, even appreciating the protection that comes with having a Grimm as an ally. With the reputation of Grimms, most creatures that recognize Nick instantly assume he is there to kill them on the spot.
Deconstructed at the beginning of Season 3. As Nick mopes in guilt after killing a man while in zombiefied state, Renard sarcastically asks him if he is feeling guilty because he killed someone or because he killed someone who is not wessen, adding, "God knows, you killed plenty of them."
The Ultra Series has several examples. While most monsters are forces of nature, many aliens have good reasons for the trouble they cause earth. Subverted overall, because the ultras are aliens.
One [[Ultraman]] episode featured Jamila, a man transformed into a monster. One of the saddest episodes in the series.
Ultra Seven episode "The Dark Zone" deconstructs the trope by having humanity kill off an entire space city of aliens to save themselves, resulting in one of the survivors trying to blow up Earth in vengeance.
Ultraman Tiga deconstructed this, featured good or misunderstood aliens a few times, in one case, one of these was brutally murdered by the humans.
Played straight (painfully so) in a later season, with a demon trying to help the sisters in return for a soul. Needlessly killed by the Big Bad before she can become human again, but after holding up her side of the bargain. And they were so close to turning her again, too. Her borrowing one of Phoebe's dresses in her last minutes showed just how ready they had gotten for it, and even caused question as to whether they actually pulled it off. This only made her vanquish even more painful.
Unfortunately however, this makes the baby fall exactly into the same category as the aforementioned half-demon Cole Turner. Despite his many attempts to genuinely reform his ways, was still treated as being inherently Always Chaotic Evil due to his demonic half by the sisters, until he decided to become evil. Score another major hit for the heroes shallow hypocrisy!
The Tomorrow People have a barrier in their mind that keeps them from (knowingly) killing. In the second story of the original series, a captive boy says that he could kill Jedikiah by sending him into magma because Jedikiah is a robot so it doesn't count as killing.
Extant: John objects to one of the board member's questions as to whether he has a plan of how to destroy Humanichs in the event they revolted by saying Ethan is his son, and questioning whether she has a plan to kill her daughter. The woman counters by saying that her daughter has a soul, to which John says there's no appreciable difference between humans' and Humanichs' brains. It soon degenerates into insults.