Hunt Her, Kill HerCAM
Donna grew up in Hibbing, Minnesota, and is the Sheriff in Stillwater, Minnesota. Due to budget cuts, her jurisdiction later extends to include Larsen County, and a few years later she appears to be the sheriff of Hibbing itself. Donna meets Sam and Dean in 2014 when they arrive hunting a pishtaco that is killing guests at a spa. After a stoned Donna blows their cover, they kill the creature and the Winchesters tell her that a "psycho killer" was responsible for the deaths.
Hunt Her, Kill HerCAM
On his way to Donna's Cabin to see his mother, Dean visits with Donna and they sit down to a meal together. Dean dodges Donna's questions about himself, instead asking about Donna, who has had a bit of a rough time since her breakup with Doug and has continued to help Jody train her adopted family as hunters. Before he leaves, Dean gives Donna a hug, making her even more suspicious that something is wrong with him.
In the beginning of Season 4, she sleeps with Angela's ex-husband, Birimbau and has trouble finding the courage to tell Angela. In The Doctor in the Den, Cam realizes that the victim is Andrew Welton, her former fiancee who she hasn't seen in 10 years. It is revealed that Cam lived with him and his daughter, Michelle, for two years before she left him. She goes to tell Michelle that her father died, but Michelle says that she doesn't remember who she is. Cam helps with the investigation by going in the field more with Booth and Brennan. She defends Andrew when the Brennan accuses him of performing surgery while in pain or under opioids. Cam goes back to Michelle to see if she remembers and Michelle tells her that she does remember her and how she left her even though she said that she loved her. Cam tells Michelle that she left because her father was still seeing other women even after she was engaged. Later, Cam is sitting with Brennan and explains why she had to leave. She tells her about the salt and pepper shaker set she got from her grandmother and how she gave her one of the shakers and kept the other one as a reminder to Michelle of how much she loved her. Brennan suggests to her that she should take in Michelle and Cam considers the idea. After the catch the killer, Cam goes back to Michelle's house and tells her. She tells Michelle that she needs a place to stay and Michelle says that she's going to stay with some cousins. Cam asks her to live with her and shows her the shaker, but Michelle runs up to her room. Cam, thinking that her answer is no, gets up to leave and makes it to the door when Michelle asks her where she's going. In her hands is the other shaker, which she interlocks with Cam's and hugs her. Cam has trouble adjusting to parenting, especially when it is revealed that Michelle has started smoking. Booth tells Cam that Michelle will stop smoking if she does (The Double Death of the Dearly Departed). In Booth's coma dream, Cam is a detective and his brother, Jared's, partner (The End in the Beginning).
At the beginning of the season, Cam struggles with hiring a replacement for Dr. Brennan because she doesn't approve of any of the candidates. Cam asks Hodgins and Angela if they think it would be a good idea for her to hire Arastoo, since they are dating. Hodgins and Angela think it's a good idea, but their conversation is cut short when Cam gets a text about a body in a van. When the body appears to be Booth, Brennan demands to work on the case and keeps finding things that Arastoo missed. Cam discovers the ring box in Arastoo's backpack and asks to see it (The Loyalty in the Lie). The body ends up being Jared, Booth's brother, and Hodgin checks up on Cam to make sure she's okay, knowing that she was close to the Booth brothers. Dr. Brennan decides to come back to the Jeffersonian, which means that Arastoo would have to find a job someplace else. Cam tells him that if he proposed she would say yes and that she would follow him in his job hunt, but he didn't want her to resent him for making her leave the job she loves (The Brother in the Basement).
At the crime scene, Brennan discovers that the corpse has something jammed down its throat. Back at the Jeffersonian, it is shown to be a coin with a picture of Christopher Columbus' face on it and a piece of paper identifying the man as Garrett Delaney, an ex-FBI agent. Brennan's brother Russ visits her, telling her that their father called warning them of danger and that he can sense that he is being watched, leading Temperance to invite him to stay with her for a few days. In Delaney's apartment, Booth and Brennan find a room filled with pictures of Russ, confirming that he was being stalked. Due to the sniper's range in the pictures, they realize that someone was hunting Russ to kill him.
Angela and Hodgins scan the piece of paper, on which an FBI agent named Gus Harper wrote that he would not help to frame a man named Marvin Beckett, a politically powerful African American rights activist whom the FBI was opposed to, and who was later sentenced to life in prison - for the murder for Gus Harper. They realize that the FBI killed Harper when he refused to help frame Beckett, then framed Beckett for Harper's murder to discredit him. Harper's wife reveals that Harper had been compiling evidence against the people who were trying to frame Beckett, and hid the evidence in a bank's safe deposit box. Realizing that her parents robbed that bank and stole the evidence, Brennan discusses this with Booth and Russ, and they realize that Russ' and Brennan's father, Max Keenan, was code-named Columbus, and killed Delaney to stop him from killing Russ.
Max reveals that Russ knew his true identity from the beginning. Brennan seems to be hurt that Max revealed himself to Russ and not to her, but Max replies that she does better without him, while Russ does worse. He explains that he didn't hand over the evidence to the authorities because his wife Christine felt that if they did, the whole family would be killed, and adds that he is constantly heartbroken by the fact that Christine died anyway. He gives Brennan the key to the safe-deposit box where he has hidden the evidence; Russ then drives up in his truck to pick up Max. Brennan tries to handcuff Max, but he overpowers her and handcuffs her to a bench instead, then moves to leave with Russ (though not before telling Temperance to hold on to the ones she can trust, that he's proud of her, and that he loves her). Booth arrives, and Max tells him to take care of Temperance. Booth starts to arrest him, but lets him escape at Brennan's unspoken request. He frees her from the fence as Russ backs his truck into Caroline's car in order to disable it, much to Booth's chagrin, then he and Max drive away. Max is then shown hanging Kirby's body and burning it in the same way he burned Delaney's body at the beginning of the episode.
Anime & Manga Attack on Titan: No one is quite sure why the Titans prey on humans. It's been shown that they don't even need to eat humans to survive. The most basic definition of an Aberrant Titan seems to be one whose persistence is predicated on some factor other than "closest humans nearby". It's eventually revealed that titans are former humans that are subconsciously drawn to eat other humans in the hopes that one of them will be a titan shifter, which will grant them titan shifting powers that will finally allow them to return to human form.
Claymore: Justified with the Abyss Eaters, as they are conditioned to crave the flesh of one particular target. Said target is much, much stronger than them, but their persistence wears him down until he dies a Death of a Thousand Cuts after months in a constant state of battle.
One of the explicitly stated differences between regular animals and monsters in Delicious in Dungeon is that monsters' urge to kill always overpowers normal self-preservation instincts. Monsters will never stop attacking until they're killed, will attack even if clearly outnumbered and outgunned by their target(s), and unlike regular animals, don't retreat if injured by their quarry or their initial attack fails.
Doraemon movies featuring dinosaurs would often depict them in this manner: Doraemon: Nobita's Dinosaur have a T-Rex who attempts chewing up Shizuka, Nobita, and a newly-hatched baby brontosaurus (which barely stood to a human's kneecaps) despite having killed an adult brontosaurus nearby, ready to feast upon. Thankfully Doraemon managed to obtain his Momotaro capsules and tame the T-Rex. From the same movie there's a whole flock of pterosaurs who relentlessly pursues the gang in an Aerial Canyon Chase for multiple minutes.
In Doraemon: Nobita and the Knights on Dinosaurs the gang encounters yet another T-Rex in an underground cavern where dinosaurs haven't gone fully extinct, and this one repeatedly tries chomping them down until it's ambushed and killed by the Naga tribespeople.
Doraemon: Nobita's New Dinosaur has a Tarbosaurus who attacks the gang in a Cretaceous Forest, repeatedly pursuing them even though there's plenty of stray Sinoceratops, Titoanosauruses and other animals around. Once more, Doraemon's gadgets - this time the Tomodachi Chocolate - saves the day by taming it.
Dragon Ball Z: Young Gohan was sent on survival training with little more than a sword. Eventually, he gets the hang of it. And apparently gets chased by a predator dinosaur every morning. Not only does the dinosaur never get Gohan, every morning he knocks him out and he slices off part of his tail and eats it. And yet, despite his prey eating HIM every morning, the gigantic critter continues to hunt Gohan. (In the beginning, anyway. Eventually, it starts running away from him.)
Enchanted Journey: The fox pursues Glikko and Nono for the entire final leg of the titular journey, completely disregarding any obstacles or dangers, and even refusing to eat the dead hawk, because he wants them.
Gyo features numerous dangerous aquatic creatures trying to prey on the human populace, but one of the most notable and driven examples is the land-mobile great white shark which attacks the protagonists, which goes to quite extraordinary lengths in its attempt to devour the heroes. Though the circumstances aren't entirely clear, this example may be justified, as the fish in question have been cybernetically (and, it is strongly implied, supernaturally) augmented for the specific purpose of killing and inflicting terror on humans; many are already dead or dying and seem more driven on by the machines attached to them rather than any natural urge to feed.
JoJo's Bizarre Adventure has a couple of these: Pet Shop, a hawk with ice powers from Stardust Crusaders. If you enter the grounds of Big Bad DIO's mansion, Pet Shop will not stop chasing you until it has removed you as a threat. His ultimate opponent ends up being another animal, who has internal monologue about this behavior being frightening and unusual.
In JoJolion, there's a Stand called Blue Hawaii. It infects the victim with a mindless, relentless pursuit of the intended target upon contact with a part of the User, ignoring their own safety to a horrifying degree. What makes this power terrifying is that it ironically still works well with groups, despite the fact it can only work on one person at a time.
Revolutionary Girl Utena featured a herd of super-persistent elephants. Where they're chasing Nanami's raft across the ocean on surfboards.
In So I'm a Spider, So What? the Anogratch are known as the "Revenge Monkeys" because if you kill even one member of their troops, its thousands of kin will not stop until they have killed you. As Kumoko found, they will literally fight until every last member of the troop has been killed.
Smirre in the anime series of The Wonderful Adventures of Nils. While he only attacks the flock a few times in the book, he becomes a recurring antagonist in the anime, who follows the geese all the way from Scania to Lapland.