There's an old story in which a boy encounters a rattlesnake. The snake asks the boy to pick him up and be his friend. After the boy does so, the snake bites him. When the boy, now dying, asks, "Why did you bite me?" the snake merely responds, "You knew what I was when you picked me up."
Some characters in fiction suffer from the same delusions. No matter how dangerous an animal is, no matter how sharp its teeth or claws are, no matter how many people it has eaten, they insist that it's perfectly safe to be around and get cozy with. Sometimes this stems from a mindset that Humans Are the Real Monsters or "we can learn so much about them", but more often than not, it leads to someone else getting killed or seriously injured.
This is a subversion of Friend to All Living Things or the Mountain Man. Compare The Farmer and the Viper which is about good deeds being repaid with evil. Characters like this usually are a Horrible Judge of Character except applied to animals instead of people, and will often be Too Dumb to Live. A character may become this if he loves animals but Animals Hate Him. May be a member of an Animal Wrongs Group. Can also be related to Nature Is Not Nice.
- In the Pokémon Adventures manga, Ruby is convinced the pack of wild Mightyena are willing to take part in Contests, even when they're attacking him.
- The Gary Larson book There's a Hair in My Dirt! is about a woman called Harriet who loves nature and doesn't understand a damn thing about it. So she goes through the woods "helping" animals in ways that make their situations worse, until eventually her lack of comprehension kills her.
- In Neither a Bird nor a Plane, it's Deku!, Izuku is fond of animals and loved "playing" (read: getting bitten, scratched, and otherwise attacked) by Katsuki's cat Dexter (who isn't a Red Lantern) when they were kids. He's still in complete denial over how much the cat hates him.
Kyouka: I'm pretty sure this cat hates you.
Izuku: Come on, that's ridiculous! I've known Dexter my entire life! Sure, he's a little rough around the edges, but he never means anything by this stuff. Things might get a heated, blood may be drawn here and there, but at the end of the day-
Katsuki: He fucking hates you, Deku.
Izuku: What? No no! No, no way. Just, just no! No but-no, come on! No way!
- The Disney version of Mowgli from The Jungle Book insists he has all the necessary skills to survive in the jungle when he clearly doesn't, and as such, he thinks he can handle animals that want to kill and/or eat him on his own. The most notable example of this is before the final battle with Shere Khan. Despite the Vultures' insistence to run away, Mowgli refuses to move. Khan probably would have succeeding in killing him, too, if not for Baloo holding him back by his tail at the last second.
- The Werner Herzog documentary Grizzly Man shows the life of Timothy Treadwell, who was one of these in Real Life (see that folder below for more info), and the horrible death that befell him and his girlfriend because Nature Is Not Nice.
- Nick and Sarah, a pair of animal rights activists in The Lost World: Jurassic Park, cause nearly every single death in the movie and almost get themselves killed several times because of their stubborn beliefs that Humans Are the Real Monsters. First, Sarah is nearly impaled by a stegosaurus when she tries to pet its baby. They then release all the captive dinosaurs, causing a stampede in the camp, and bring a wounded baby ''T. rex'' back to their lab to nurse it back to health. This turns out just as you'd expect, and they get an innocent character killed and lose their radio equipment (along with their entire lab) in the process when Mama and Papa Rex come for them. This forces the rest of the characters to hike through raptor territory in order to reach the nearest communication source. And to top it all off, Nick unloads the hunter's gun and removes their only practical means of self-defense by doing so.
- The events of 28 Days Later were kicked off by a bunch of animal-rights activists liberating a bunch of infected monkeys from a lab.
- In Elf, Buddy runs into a raccoon and goes over to pet it. The raccoon hisses at him, but Buddy thinks he just needs a hug. That's when the raccoon attacks him.
- In Prometheus, a character finds a snake-like creature who is obviously acting in an aggressive manner but still decides to get in close to touch it while calling it "baby". It doesn't end well.
- In Man's Best Friend, the heroine rescues a large and seemingly friendly dog who was being experimented on. Unfortunately the dog is incredibly dangerous and kills several people before the end, although the ditzy 'heroine' escapes completely unscathed.
- Ward in Dragon Bones is thought (partly due to his Obfuscating Stupidity) by other characters to be this with regard to a very vicious horse, but in fact is really a Friend to All Living Things, as he knows his way around horses and the horse in question is actually not so much aggressive as ruined by his violent father. The horse actually killed his father, but Ward decides to keep it and give it a cutesy name.
- In Masques, Aralorn does something incredibly stupid ... she rescues a wounded wolf from a pit trap. Subverted, as she can magically calm the animal down ... and it wasn't an actual animal, anyway. "Wolf", actually a magician in disguise, becomes her friend.
- Hagrid in Harry Potter, who is known to befriend all sorts of dangerous beasties, from dragons, to flesh-eating books. Although they really don't harm him (much), his monsters are often a danger to the heroes. This is at least partly because he doesn't fully grasp just how much stronger and more resilient he is from most humans; most of these things legitimately don't pose much threat to him.
- Referenced in The Colour of Magic:
(Rincewind) always held that panic was the best means of survival; back in the olden days, his theory went, people faced with hungry sabre-toothed tigers could be divided very simply into those who panicked and those who stood there saying "What a magnificent brute!" and "Here, pussy."
- In the first season of Primeval, a woman found a Smilodon cub that had fallen through an anomaly and decided to adopt it. She thought that because he saw her as his mother, he wouldn't harm her. When she tried to sic him on the protagonists, he attack and killed her (then attacked the protagonists).
- Canary in Phantom Brave creates a monster rights group called "Human Activists for Rare Monsters". Its acronym is also what the average monster wants to do to Canary.
- An early quest in Xenoblade Chronicles X has an Interceptor named Carl task you with clearing a cave of indigens, but balk at the prospect when it turns out the beasts in question are all young. You're given the option to spare them, in which case they come back later in the game, now grown up and very hungry, and kill several BLADEs in their rampage — including Carl himself.
- Stand Still, Stay Silent has a gag in which Reynir goes to check on Onni in the dreamspace after the latter contributed to a battle long-distance, finds an animal in Onni's protected area, pets it assuming it's Onni's luonto and finds out it's actually Onni in his luonto form. Onni's luonto is an Eurasian eagle-owl, which it just what it sounds like and an animal nobody with half-decent survival instincts would want to pet, even it can be presumed to be benevolent to an extent.
- In Noob, a running gag is to have the Kindhearted Simpleton who likes collecting pets think he can do the same with enemy monsters. The story is set in a fantasy MMORPG, so game mechanics are quite clear-cut on what is here to be adopted as a pet and what is here to be killed for experience points. The only exception is one species that has been shown to be subject to Pet Baby Wild Animal.
- In the South Park episode "Rainforest Schmainforest", a Costa-Rican tour guide reassures a frightened Stan that coral snakes are more scared of humans than we are of them — just before the snake attacks him, swallows him whole, and poops him out in a matter of seconds.
Mrs. Stevens: Jesus Christ, is he dead?!
Kyle: My guess would be yes.
- Leela in Futurama is this way.
- In "The Sting", she gets Fry killed although it's just a dream by bringing a killer space bee aboard the Planet Express because "it's so cuuuutteee!"
- In "Bender's Game", she refuses to save her friends from a giant worm called the Tunneling Horror because she has just vowed to never kill another living thing.
- Elmyra Duff from Tiny Toon Adventures is both an idiot and and animal lover. It doesn't matter if the animal is ferocious and has sharp teeth and claws, her undying love for them keeps her quite oblivious to how dangerous they are. When she does manage to get her hands on them, the animals find out from the way she treats them that she's even more dangerous than they are.
- An Animaniacs sketch ("The Hip Hippos") involves a Jane Goodall Expy maintaining vigilance over a pair of City Slicker, Nigh Invulnerable (because of their obesity) Idle Rich hippos. The Running Gag is her seeing them in (what she believed to be) danger and try to save them, only for the hippos to come out of the stunt all right and her hurt in some comedic fashion (with them not even noticing she was there).
- The Simpsons: In "The Squirt and the Whale" after failing to save a beached whale, Lisa tries to save its pod of offspring from a group of sharks. But then she learns An Aesop that sharks need to live too, and in order to live they eat other animals — such as baby whales.
- Bubbles of The Powerpuff Girls. A friend to just about every creature great and small. Magnified in "Helter Shelter" when she brings a beached baby whale home.
- While Fluttershy of My Little Pony: Friendship Is Magic is usually good at dealing with animals, she becomes this in "Swarm of the Century" when she decides to adopt a cute parasprite, which then multiplies and very nearly destroys Ponyville by eating everything (even buildings) in sight. After Twilight and the others have found a way to rid the town of the parapsprites and are congratulating themselves on a job well done, what do they find but a new colony in Fluttershy's cottage. She couldn't resist keeping one, despite knowing the damage that they cause and the fact that they breed like tribbles.
- SpongeBob SquarePants has quite a strong admiration for jellyfish (which this show treats as an undersea equivalent to honeybees), but this ends up biting him in the back a couple of times. In one episode ("Jellyfish Jam"), SpongeBob decides to take one home as an exotic pet, believing that he can tame it. In another episode ("Nature Pants"), SpongeBob decides he wants to live as a wild man alongside the jellyfish in their natural habitat. But on both occasions, SpongeBob eventually finds out the hard way that the jellyfish are aggressive, ill-tempered, wild animals that don't really care for him.
- Timothy Treadwell wanted to spend some time in the wild living with grizzly bears in Alaska, in an attempt to show the public that the animals are not the murderous monsters everyone believes them to be. While he survived that experience, he and his girlfriend did not survive their later encounter with a brown bear. Also see the documentary about this called Grizzly Man.
- Obviously, this happens a lot in real life. Sometimes nothing worse than a bad scare comes of it, sometimes the consequences are downright tragic, and everything in-between. Even animals that most people see as harmless - deer and rabbits, for example - can cause painful and even serious injuries if they feel threatened.
- In 2003, the Eco-Terrorist group Animal Liberation Front freed and released 10,000 minks from a fur farm. Minks are just cute harmless rodents, right? Nope, they're vicious predators. Once they were set free, they hunted down and killed numerous animals in the area, including dogs, ducks, chickens, and fish on a nearby farm. When they were recaptured and put back into cages, many of the minks killed and ate each other (a mink can live peacefully with its family members, but the farmer had no way of identifying which of the recaptured minks were related).