Several years back, there was an ad campaign for Beggin' Strips dog treats that had several people giving the treats to their pets. As their dogs cutely ate them, they basically dissolved into baby-talk and cute overload.
A woman and man do this in a McCain commercial... to a bag of baby peas. Cue raspberries and the inevitable cooing. Ick.
Occurs during the Bount arc in the anime version. When a decision needs to be made about which person each of the three mod souls would be paired with, Rukia (the possessor of a long standing rabbit obsession) positively melts over the plushie (a rabbit-like purse) inhabited by Kurodo.
Rukia shows her love of bunnies again in chapter 464, when she has to fight Riruka in a place full of plushies. Several of these are bunny-shaped. This happens. And in a subversion... in 469 this proves to be a flaw. Rukia cannot really concentrate in her fight due to the adorableness of the plushies, which gives Riruka a chance to attack.
Roy Mustang apparently had this occur over dogs. Although, he states that he likes dogs because you can "Be a jerk to them and they won't complain and they never once beg for a paycheck!"
"Well, you're awfully manic today, sir"
Also, Al's reaction to kittens, while in character, probably counts, especially as he looks scary.
When Scar (that's right, SCAR) first gets a look at Xiao May the panda, he's so overcome with cute he wants to pet it! It was only shown once in an easy-to-miss scene in show, and once in a non-canon "4-Koma Theater" episode, but it's still freaking funny.
Maes Hughes was regularly seen bragging about his cute daughter Elicia (After being exposed to her cuteness, Winry has similar symptoms)
"Yep, you're the same as ever, Major, nice and insane."
And about his wife Gracia, too, although less frequently.
Winry has exactly the same reactions at the sight of well-done automails and mechanical supplies. The start of episode 11 of Brotherhood shows this very well.
Inubaka: When Suguri started passing out fliers for Woofles, Noa helps out. She goes over to two tough looking guys, who ask Suguri menacingly if it's her dog. Suguri nervously replies it's the shop's...cue 'here boy's and 'aww, he's so cute's.
Sakaki, over pretty much anything. Unfortunately the animals involved REALLY don't appreciate it. Also, she can be internally overwhelmed by all the cuteness, but all the other girls can see is a blushing Huge Schoolgirl.
Crazy Awesome badass Prussia falls victim to this when he finds a baby chick on his head, commenting on how soft and fluffy it is. His little brother Germany, normally The Stoic, has a weak spot for dogs.
While not really uptight, China is a reasonably composed guy who tries to act as a Big Brother Mentor to the other Asian nations and often plays Only Sane Man to the other Allied Forces, but he has a definite weakness for cute things. Hello Kitty plushies, pandas, baby!Japan or anything else he thinks is cute, can easily cause him to dissolve into bubbly giddiness.
Miu Fuurinji and Kisara Nanjo absolutely adore cats. Kisara especially to the extent that she adapts cat-based movements into her Tae Kwon Do fighting style, which another character promptly calls Nya Kwon Do.
Kisara's Cuteness Proximity is deconstructed twice, albeit in two very different directions. First, when she is sheltering a cat from the rain, the Valkyri choose this moment to attack, knowing that she can't fight them all at once while protecting something. Later, after she has officially left Ragnarok, Nijima tries to blackmail her by threatening to release pictures of her being adorable with cats, ruining her tough girl image. Siegfried rejects this plan, coming up with an alternative.
Siegfried: In return for your friendship and loyalty, we offer...THIS ADORABLE KITTEN!
Kaido Kaoru of The Prince of Tennis. While he doesn't quite "disintegrate into a pile of gloop", the most antisocial member of the team attempting to play with a cat while still coming off as intense and a little scary was hilarious in its own right.
RahXephon's Haruka Shitow takes all but two seconds to shift from, "One more step and I'll shoot!" to "Daaaaaw, it's so CUTE! can we keep it? Pwetty pwease?" upon encountering a stray cat in the third episode. An especially good scene, because in those two seconds she mentally jumps 12 years back in time... and into a completely different dynamic. Ayato has NO idea what's going on.
Misty slips into this when a stray Teddiursa wanders into their camp and looks her in the eyes. Of course, once they find out it's been scarfing down all their food behind their backs and making Ash's Totodile take the heat for it, the little thing seems much less cute. Even better: it continues to try to invoke this trope after it evolves into the much more feral-looking Ursaring.
Marilyn, a one-off character in the episode "Battling a Cute Drama", to a truly ridiculous extent. Brock is annoyed to no end by it.
This is actually an interesting case to study than it sounds. Brock was more annoyed by Marilyn for her ridiculously strick standards of Pokemon cuteness - must not be too high, must not be evolved, etc. - because it was a shallow perspective that put lesser value on other Pokemon. When she comes to understand, she admits that her favourite Pokemon, Shellder, had led to her being put down by her peers and she adopted the viewpoint in order to fit in. When she comes to understand the deeper inherent qualities in a Pokemon and how they too can be admirable as well as cuteness, she... doesn't stop gushing over her favourite Pokemon, ut realises that having a different perspective isn't bad and stops being ashamed of herself. Brock is, naturally, pleased to hear this.
The first thing Ash ever said about Pikachu was "It's so cute!" (He was then promptly electrocuted.)
Zoro in general appears to have soft spot for cute things, especially Chopper.
The Puchuus in Excel Saga are an alien race that are able to conquer planets because no one can resist their cuteness. Oddly, it seems only men are affected, though the only women we ever see them encounter are a really crazy girl and the only serious person in the whole show.
Yuno of Hidamari Sketch stops in the scavenger hunt to pet the dog, and even petted drawing brushes when she thought of the animals the bristles came from.
Examined in Super Cruel and Terrible Tales of Mangaka. A young mangaka is very passionate about gory, gruesome manga, and is very, very happy in terms of success. However, when his wife gives birth to a daughter, this trope settles in, and the quality of his manga fades and eventually gets canceled. ("I don't need status or glory, or money or life, as long as I have Nunuko!")
Ando, from ChocoMimi may look tough, but he has a soft spot for cute animals, especially Picho, his pet bird. Worth noting is that he once randomly hugged Jin simply because Jin was wearing a raincoat that made him resemble Picho.
Yuiko from the manga Beast Master takes this Up to Eleven whenever she sees a cute animal, such as a dog or a cat, and even birds.
Little Sister Misaka in To Aru Majutsu no Index, though it's slightly more subtle due to her normalinexpressive personality. The clearest example, though, can be seen when she is helping take some cans back to Touma's apartment and runs into Himegami and Index taking care of Sphinx, and the entire time her eyes are twitching back and forth, following the cat's tail. She even has little blush stickers on her face!
Heartcatch Pretty Cure has MyoudoinItsuki, whose mature and reserved facade instantly crumbles at the sight of cute dolls or frilly clothing. She initially tries to hide this habit, out of concern for herimage, but she's slowly getting better.
At one point during Digimon Tamers, Tally and Riley pick up a strong Digimon signal... only to look down and see that Calumon's wandering around the control room. Riley basically ignores him, but Tally immediately notes how cute he is. Many viewers agreed with her.
Calumon: Calumon, zoom zoom, here a zoom, there a zoom! Calumon, zoom zoom, NO UNDERWEAR, ZOOM!
In one episode of Chi's Sweet Home, Chi sneaks into Dad's bag when he goes to meet his bosses at work, and she comes out when he's presented with sample food (he's a designer). Instantly, The Comically Serious starts petting and speaking Baby Talk to Chi.
The real example is the pet store worker who constantly obsesses over Chi and wants to take her home. She even visits Chi at the Yamadas' house (whom she barely knows) when she finds out she already has a family.
An early episode of Sailor Moon featured a plot to drain people through adorable little pets. When close enough to them, their pheromones trigger this result in anyone. Luna realizes the whole thing is off when Usagi and Shingo are so enamored with the creatures that they actually yell and kick at her if she tries to come close to them.
Syaoran's older sisters who appear in the 1st Cardcaptor Sakura movie. They gush over Sakura and Tomoyo... until Touya and Yukito arrive, at which point they switch to gushing over the guys. (Syaoran is exasperated by this.)
Asobi Ni Iku Yo has a Ninja Maid named Sarah who reportedly made it into the SAS but washed out soon after due to her love of small, cute things. Her current employer is a girl who runs a cult dedicated to worshiping cat-people.
In Popcorn Avatar, Lisa finds Mafuyu adorable. Since Mafuyu is Kurando's twin, one wonders if she feels the same for the latter.
Taki from Natsumes Book Of Friends finds Nyanko-sensei to be so adorable she can't help glomping him. Given that everyone else considers Nyanko-sensei to be "Natsume's ugly cat", her taste in cuteness is questionable.
In an issue of She-Hulk, the title character visits a prison where supervillains are shrunk down before they are incarcerated. She starts cooing when she sees the tiny Wrecking Crew.
She-Hulk: Who's the cutest little Wrecking Crew? You are! Yes you are!
In Gold Digger, the ancient civilization of dragons tend to be sharply divided on their opinion of humans. Some find the idea of a civilization of little, vermin-sized mammals disgusting; but at least as many dragons, if not more, find us adorable, seeing us sentient mammals essentially as a race of little bunny people. This us why so many of them choose to shape-shift into human form; so they can secretly have fun hanging out with us in our cute little bunny village "cities."
In one of the early Sunday strips, Daryl and Zoe are passing by a fat construction worker, who's yelling over the noise of a jackhammer and swearing like a sailor... Until he spots Zoe in her little stroller, undergoes a complete personality shift, and coos to her like a mother. In Daryl's words to her, "How do you do that??"
An early story arc revolves around Daryl suddenly finding himself unable to stop using baby talk. Wanda digs up a baby book which explains that this condition is commonly brought on by babies' cuteness and recommends "exposure to the baby during peak non-cute periods" as the cure.
Daryl: Wot's dat 'posed to mean? Wanda: It means you get the night shift, Tweety Bird.
An entire Bloom County story arc consisted of Oliver making contact with a race of aliens planning to enslave much of Earth's human populace. Now they may have had flying saucers with lasers and the like on them, but their biggest advantage by far over the humans was that all of them took on the shape of puppies with big innocent eyes. Said arc was making a serious political statement about how Oliver North was handled with kid gloves at a Congressional hearing.
Bo from BoNanas once asked his roommate to put him on a leash as they went outside, trying to make a message on how wrong it was for him to be constrained as a mere "cute" animal. Naturally, once they begin their stroll, every stranger they encounter can't help but gush and babytalk him. "... Well, you are cute." "It's my curse."
Marik: I shall defeat you and then conquer the world! Ahahahaha, Ahaha! Oh, hey, look, a bird! Isn't it just the cutest little guy? I mean, No! I-In my new world, all birds shall be enslaved! Especially this one, and he shall be named, Mr. Tweetums! For it is very evil! Ahahahahaha! Now be gone, Mr. Tweetums! I am trying to stalk my nemesis!
And later in Episode 43 even his evil alter ego, Melvin, is shown to have a soft spot for the bird.
Melvin: I hate to burst your bubble but there's no-one in my head worth remembering... NO! Mr. Tweetums! I can't forget about him!
When Kyon sees Hanyuu in Kyon: Big Damn Hero, he has to resist commenting on how cute she looks.
Played straight with Apple Bloom and the Judge. The Judge thinks she's the cutest thing he's ever seen, and he becomes very protective of her while she's on the witness stand, causing a few problems for Phoenix.
Subverted via sarcasm in TMNT 2007 when Ralph comes across the Jersey Devil.
Raphael: Oooh, ain't you cute? You want a butt-kickin' little fella? Yes you do, you do! C'mon, I'm gotta drop kick you to hurty-town.
The How To Train Your Dragon short "Gift of the Night Fury" features a scene where an egg that is Made of Explodium goes off and shoots out an adorable baby dragon. All of the Viking kids present save Astrid gather around it to coo, not giving a thought to the eggs being a) explosive and b) distributed around town.
In The Dresden Files, the current Archive is a human girl (Nicknamed Ivy by Harry.) with magical access to everything ever recorded by humanity, as well as the combined memories of all previous Archives. She is articulate, mature and scarily powerful, and when she states that if Dresden backs out of his duel she'll take it personally and kill him, Dresden realizes she is fully capable of doing so without breaking a sweat. But when Dresden's cat Mister suddenly appears, she shouts "KITTY!" and starts playing with him, making you realize she's still a 7-year-old girl. Her bodyguard (a Half-Human HybridSociopathic HeroCombat Pragmatist with a thing for explosions)'s reaction to this: "Now that is scary." Mister is the size of a small tiger and isn't above pushing Harry around, but he seems to quite like Ivy. Maybe a little of this goes both ways.
Lord Vetinari's usually very reserved aunt Lady Roberta Meserole does this whenever her lapcat is around — as does Vetinari with his own dog to a lesser extent. When we see teenage Vetinari (i.e., before he gets the dog), he finds his aunt's devotion to her cat extremely irritating. He also thinks that if she's going to have a pet, it should be a long-haired white cat which she could stroke in a sinister way.
Nanny Ogg as well. She does this with babies (many of which, in Lancre at least, are her descendants) and with her evil one-eyed demon cat Greebo.
Due to male and female dwarfs looking alike, Sam Vimes is still not sure how many of each he employs. Until his infant son is brought to the Watch House, and half of them can't help but fawn over him.
Even Granny Weatherwax's hard outer shell softens around the kitten she named You. She places her on her head, under her hat; she claims it's to keep her head warm, but really, is anyone buying that?
In the short story "Hell in a Handbasket", any demon who comes across the baby in the story is forced to do this, whether it being intentional (Vassago), to being physically unable to harm the child and forced to talk in baby talk (Harpy).
An entry in Chicken Soup for the Pet Lover's Soul features the author (a new cat owner) fearing she's become "one of those people" who use baby talk on their pets. Naturally she succumbs to it in the end.
French writer and journalist Robert Beauvais provided a humorous study of the language used by dog-owners, which he dubbed "le kiskose chien-chien" ("the doggy-doggy whatchaspeak"), in Le Franšais kiskose (1975).
When Tash and Zak find a baby in Galaxy Of Fear, they don't dissolve too far into babytalk, but they do say sillier things than usual.
At the end of the Warrior Cats novel Crookedstar's Promise, the jerkassegomaniac Beetlenose comes flying out of the Nursery, squeeing about how cute Crookedstar's daughter Silverkit is. Keep in my that he's a cat, and even he found her cute.
In the episode Colossus Against the Headhunters, this is the reason for Nummy Muffin CoocolButter's existence. Dr. F's idea is that everyone who comes in contact with Nummy will be so overcome by his cuteness that Dr. F will be able to take over the world. This works on Mike, although the 'bots are only annoyed by Nummy and his constant shedding. But when Mike notices that Frank and Nummy miss each other, he sends Nummy back to Deep 13, and Dr. F falls into his own trap.
A minor Running Gag has the guys react to any dog appearing in the movie they're watching by cooing "Puppy!" and trying to get its attention. Even if it's supposed to be the monster of the film.
Arrogant, Narcissistic painter Olivier in Six Feet Under turns to pudding when he meet Brenda's baby.
Kelso laughs at Elliot's attempts to be unfeminine by saying that as soon as the "stork comes calling" she'll be gushing "look at the baby!" like all of the other female doctors in OB/GYN and Pediatrics. She denies it, but when she actually sees the baby...
The same thing happens in a later episode when she and her friend Melody are shrieking with joy (to such a degree that in J.D.'s fantasy they are actually blowing people away). Showing them a picture of Turk's daughter Izzy immediately turns their screams into "Aww"s.
We're not exactly sure how to spell the string of gibberish that Burt Campbell spouted off whenever he was faced with his granddaughter Wendy. The letter "L" would definitely be used heavily, though.
Burt's son Chuck&Bob (Chuck was a ventriloquist), who was Wendy's step-uncle, would stick Bob's head up close to hers and go "WenyWenyWenyWenyWeny! WenyWenyWenyWenyWeny!" while shaking his head back and forth. Chuck is usually slightly embarrassed by Bob's behavior.
The straight-laced businessmen on The Fast Show, who get soppy over calenders with cute puppies on them and excited when they're allowed into the cockpit of a plane.
Data: He will need to be fed once a day. He prefers feline supplement number 25. Worf: I understand. Data: And he will require water, and you must provide him with a sandbox, and you must talk to him. Tell him he is a pretty cat, and a good cat... Worf: I will feed him.
It seems to be sort of an unspoken rule in Star Trek... If you're supposedly emotionless, you have to love small furry creatures, especially if they're cats.
Star Trek: Deep Space Nine: In one episode, O'Brian is bringing his baby son to work because if he sets the child down, he'll start wailing. At the end the baby grows out of this, falling asleep in his carrier. Sisko tells O'Brian to take a few days off, then reminds every female officer in Ops (including Dax and Kira) that they have jobs to do.
Margaret: Did you tell the Counsel's office that they would be in on the 10 o'clock? Leo: I may have. Margaret:(miffed) That's really something that you want to tell me. Leo:(showing photograph) Here, it's a baby and a new mother. Look at that for a minute. Margaret:(reacts in traditional manner)
Lampshaded quite neatly on Friends when Joey gets a dog. When Rachel sees the dog, she dissolves into Baby Talk, par for the course as far as this trope goes. She then realizes it, and says to the dog, still in Baby Talk mode, "I really have to stop talking like this before my board meeting, yes I do! Yes I do!"
Daisy does this a lot with her dog Colin in Spaced. Downstairs neighbour Brian attempts to talk to the dog in a normal and reasonable tone (after inadvertently sitting on him) but this proves unsatisfying to Daisy, who forces him to adopt a cutesy and high-pitched voice when talking to the dog for no readily explainable reason.
Both Brian and Marsha initially appear to have a more mature and responsible attitude toward the dog, but they pretty quickly break down into dressing him in an Edwardian ruff and making him dance. Also, Colin's Cuteness Proximity actually becomes a plot point, when it becomes an issue of conflict between Daisy ('How can you not like him? He's so cute.') and Tim ('That's how it starts, with 'oohs' and 'awwws', but soon there'll be barking and... biting...'). Due to Tim's childhood caniphobia (which is not the fear of bamboo) he is immune to Colin's head-cocking adorableness... until he bonds with the dog rescuing him from freelance animal vivisectionists and is nobbled by the dog as much as anyone else.
Subverted and Lamp Shaded by Roz in Frasier when Frasier attempts to get her to adopt a puppy.
Roz:(cooing) Oh, he's adorable! Oh, come here, little fella! Oh. Aren't you the cutest little thing? Oh, yeah. Give me a kiss. Give me a kiss. Oh! I love you too. (shoves the puppy back to Frasier, harshly) There. Happy now? Frasier:(aghast) Roz, how can you just toss him aside after such a tender display of affection? Roz: I do it with men, too.
M*A*S*H: Charles Winchester reacts this way to the half-Korean, half-American Doorstop Baby that gets temporarily taken into the camp while they searched for a proper home for her. And this was Charles.
Dr. Talbot on Mercy reacts this way to a kitten she finds under a car. Her accent makes it all the more hilarious.
Gillian: Ooooh look, it's a poor little stray urchin!
And flying alien fish, to the point of talking Baby Talk to them.
The Doctor also exploits this trope. In "Closing Time", he gets Craig to bring his baby son with them when they investigate the alien-menace-of-the-week. His reasoning is that people are friendlier to someone with a baby, which is the same reason he travels with non-Time Lords.
"So I'm your baby?" "You're my baby!"
It happens to the Doctor again in "Dinosaurs on a Spaceship"...with a triceratops.
In Monty Python's Flying Circus, a woman affected by this trope, and babbling appropriately, makes the mistake of removing the baby's pacifier. Everyone in the room is sucked into the vortex.
One episode had Marshall, Lily, and (eventually) Robin, and Barney gushing over a baby's sock.
Worse yet, the tea cup pig wrapped in a blanket. Just watch Great music at the end there.
On Bones, Dr Temperance Brennan suffers from a modified version of this. Although initially a bit uncomfortable interacting with an abandoned baby she and Booth found during a case, she is soon cooing and playing with it — in a very Bones fashion. In one memorable bit that she repeats in later interactions with babies in the series, she wiggles her fingers in the baby's face (to its delight) while chanting "Dancing phalanges! Dancing phalanges!"
In the Season Six Halloween Episode of Buffy the Vampire Slayer, Willow's rant about witch stereotypes is cut short when she notices the utterly adorable four-year-old in a witch costume. She pretty much melts.
Conan O'Brien had a wildlife expert on as a guest, and completely lost it when he brought out the coyote puppy. As the animal guy was trying to explain they're "less friendly than dogs and wolves" Conan was rubbing his cheek on it. Then it licked him. Then he licked it back. The bear cub did not quite elicit the same reaction, as it was trying to claw him to death...
On Parks and Recreation everyone in Pawnee, including (make that especially) the ultra-manly Ron Swanson, is enamoured of Lil Sebastian, a miniature horse considered a local celebrity. The only one in the cast who isn't is Ben, who just sees a small horse who doesn't do anything (To be fair, he is from out of town). When Sebastian dies, his funeral becomes a major event, and even Ron is moved to tears for, he claims, only the second time in his entire life.
The gruff and withdrawn Nathan Wournos from Haven pretty much turns into another person around babies.
Supernatural: Dean's theory why his brother is so much better in convincing people of the crazy, spooky ghost hunting stuff is based on comparison of Sam to a big puppy. (well, at least in the first few seasons.) Thus reducing the unwitting civilians not necessarily to a melting mass of Baby Talk but getting them to listen to them. Which is definitely more helpful.
Played for Laughs when Girls Aloud invited a special guest over on their Christmas special. The girls got so excited to meet Paul O'Grady's dog that Nadine took him right out of Paul's arms when the two showed up at the door. An offended Paul then takes the dog away from them and threatens to give their Christmas presents to the Sugababes.
French singer Richard Gotainer wrote a whole song — "Le Youki" — in baby talk, precisely to mock this habit of dog owners. You can find the clip there (and you probably don't need to understand French to get the gist of it). Warning: Ear Worm (and slightly NSFW too).
In the Psychostick song 'We Ran Out of CD Space', various strange scenarios are posited, including the following example of this trope:
What if your room was filled with lots and lots of puppy dogs? You would be like "Aww, look at the puppy dogs! Awwwwww, come 'ere! Come 'ere! Awwwww! Whatcha doin little guy? Whatcha doin? Ooh whatcha wookie-wookie! Who's the puppy dog? You're the puppy dog! Who's the puppy dog? Little puppy doggies!"
Lucy the Bulldog. She was the pet of Triple H, and he walks on screen, picks her up above his head, and says something along the lines of "Schnuzzywuzzywoofle". Funnier than it sounds. Woulda been even funnier if Lucy hadn't been upstaging the guy HHH was theoretically feuding with, Chris Jericho.
Pepper. Al Snow, he who carried around a mannequin head named Head, had lost Head. He found a little chihuahua to replace him. Al brings the dog out for one of his matches and leaves him in the care of announcer Jim Ross. Ross quickly became more interested in the dog than the match, and was very displeased with how much the loud crowd scared the dog. Pepper was almost immediately thereafter retired from television — by being kidnapped, cooked and fed to poor Al by the Big Bossman.
Happened again with Rene Dupree's poodle, Fifi. Ross would talk about how terrified the dog was (Dupree being a heel) but whenever the camera was on her, she'd be stood on her hind legs, happily being fed popcorn by fans.
Super Robot Wars Judgment has Bonta-kun, a mecha that was already cute in its source canon. And, while it's a surprisingly decent if not outstanding combat unit, it's defining trait is causing many villain characters from other series to find it adorable. In fact, it's ability to induce Cuteness Proximity is so pronounced it can even affect RauLe Creuset.
Chibiterasu, the protagonist of Okamiden. Full stop. I mean come on, even SAKUYA melts when she sees him. To be fair, anyone would melt◊.
Tear Grants of Tales Of The Abyss did this, although to a slightly lesser extent: She didn't completely lose her dignity, but cute things at first were the only indicators of her softer side. She shows it more in the anime adaption.
Princess Sapphire from Disgaea 3: Absence of Justice has a thing for anything "cutesy". Like, for example, Raspberyl. One instance in the main story had a teddy bear out in the middle of Team Mao's path. Almaz rushes out ahead of Sapphire to pick up the bear, only to get jabbed by the trap inside and subsequently cursed to die. The trap had her name on it, he knew it, and he went to intercept it anyway.
Makoto: Hey, look who's here, it's Tao! Aren't you just adorable? Yes you are, yes you are! Taokaka: Furry tail girl! Your tail is so fluffy today too! Furry furry furry furry furry ooooh... Litchi: You two are like animals. Noel:(Heart Symbol) ... Aaaaah...
The funniest example is a young Ragna descending into this upon meeting Jubei. This was before he became the pissed-off Good Is Not NiceAnti-Hero we know today, but still...
Leliana: I saw you playing with that kitten and dangling string for it. Sten: I was helping it to train. Leliana: I knew it, you're just a big softie. Sten: Stop saying that. Leliana: Softie!! Sten: I hate humans.
This actually becomes a bit of a Running Gag if Sten and Leliana are both in the party. Another brilliant example is her catching Sten picking flowers (for medicinal purposes).
And from the Awakening expansion, you can get a kitten as an inventory item. Click it, and Anders the mage coos "Whooo's a pretty kitty?" and similar bits of cuteness overload.
Touka from Utawarerumono, melts when the weasel... rabbit... Nidoran thing that lives with Aruru gets near and does a poor job disguising it.
In Planescape: Torment the protagonist can find an action figure. One dialogue branch regarding the "toy" has the protagonist devolve into an excited little child detailing the adventures of the heroic figure. At least one of your sidekicks severely disagrees, after which the action figure "agrees" that he's a jerk.
Morte: I'm gonna smash that Modron cube to bits. Nameless One: Did you hear anything, cube hero? Neither did I!
World of Warcraft's Mylune is a dryad with a rather... bubbly personality. She can't so much as talk about "the wee animals" without devolving into baby talk and incoherent squealing. It's difficult for the fans to not have this reaction to Mylune herself.
Saber in Visual Novel/Fate/stay night for lions and stuffed animals. Played for a joke initially and then used as fuel to tear her emotional fašade apart. It's what she would normally be and would like to be if she didn't have to be King Arthur and whatnot.
Belkar also falls victim to this trope, after a fashion, in that Mr. Scruffy is the only living thing he'll show any sort of empathy for. Though that's mainly because, as a freaking cat, Mr. Scruffy is not only cute but also totally Badass.
In RPG World, one time badassAction Girl Cherry, left alone with Dragobo, took a quick look to each side before giving him a giant glomp. (Arguably, her reaction to Hero also falls under this category).
Marigold's Anthro-PC Momo (who looks like a little girl anime character) has this effect on Dora, as seen in this strip. Apparently its a common enough occurrence to warrant having a taser feature built in to shock them out of it.
Hannelore has a different sort of reaction to cute felines. Hilarious since Mieville pulled the Cats Are Mean card in the previous strip.
Sniper Wolf: Aren't you ze cutest? Yes you are! Yes you are. Berthold: Fantastic, she's a grandma.
In Freefall, upon first meeting Florence, an uplifted wolf, robots have a tendency to immediately shout "doggy!" Every robot. This is because they're not programmed witha proper greeting for Bowman's Wolves, so they have to use the first greeting she received after arriving on Jean... which came from Helix.
Quite a few of the Let's Players own pets who like to vocalize or otherwise annoy their owners at an in-opportune time.
Lord Vega, for example, has had at least one terror-laden blind run of Silent Hill interrupted by his cat.
Deceased Crab has had mixed reactions to his kitty peeking in on him during his recordings. From irritation ("Begone, kitty! I'm trying to Shadowrun!") to your basic "Aww, you're a good kitty". (And, of course, the one time he tried to get his cat to meow on cue, the cat refused to cooperate.)
Also when he and MadamLuna LP'ed Shadowgate Luna ended up cooing over a Sphinx.
Subverted in Let's Play Super Castlevania IV, where the apparent stimulus for Belmont killing Dracula was the death of his kitten, Fluffer Butter Waffle Nut. Naturally, the more the cat is discussed, the further into madness the speaker tends to descend...
HC Bailly tends to play a lot of games with cats in them. Perhaps the best example of this trope was in Let's Play Chrono Trigger when he started collecting cats and starting off several episodes with an excited "and we got another kitty! Yes! Yes!"
Frankomatic has his cat interrupt him during several inopportune moments during his LP's, most notably in Donkey Kong GB:
There's a cat jabbing its claws into my leg; let's see if that helps my playing ability any! Please stop, Tommy. [drops off a platform in the game] Oh God! Clearly it does not help my playing ability in the least! Do you see what you're doing to me, cat? Seriously, cut it out!
Gronkh frequently parodies this in the interaction with his Minecraft dogs.
Chorocojo Roxy went into a coma due to Cuteness Proximity Overload at one point. This trope is her hat, the same way that being a gamer girl is Sammy's, being a rage-spewing badass is Misty's, being the Only Sane Man is Lady's, and being a sexy chick in a land full of rapey-rapeys is Roxy's cousin Foxy's.
Although he is typically immune to overt cuteness (see his reaction to Full House), the Critic fell completely into this trope when watching Sesame Street, due to his childhood love of that series. He can't even finish the review.
SCP Foundation: "SCP-2558-J has displayed the ability to distract people far more than merited by being kittens, even considering their anomalous abilities. Suggested reclassification as Euclid." An even greater sign of the power of cuteness in these things: after an experiment resulted in grenade versions of the kittens, there was a resolution signed to prevent further weaponization of the creatures. That's right, the SCP, a group that goes through expendable manpower like popcorn, refusing to let harm come to kittens.
Board James (and his co-host, "Motherfucker Mike") had this response when he first saw the Doggie Doo dog.
In an episode of The Simpsons where all the guys are in the Navy for some reason and their sub is filling up with water, their thoughts go to their loved ones and in Moe's thought balloon he's stroking his kitty and talking baby talk to it before angrily turning to the audience shouting, "What are YOU lookin' at!?"
Mr Burns attempts to invoke this, along with All Girls Love Ponies by bribing Lisa with a trio of cute ponies called Sugar Belle, Honeysuckle and Dew Drop.
Whenever Fred Flintstone, normally a rough-around-the-edges Ralph Kramden-type, sees his daughter Pebbles, he goes all sweet and cute Bumbling Dad and starts to gush about his "little Pebbly-poo".
King of the Hill: Hank Hill has a mild case of this for his dog Ladybird. While an old dog, she is one of the few living things that the emotionally repressed Hank will show open and adoring affection and emotion for. Also his father Cotton, a gruff misogynist even more emotionally closed off than Hank, is similarly adoring of his baby boy Good Hank.
The series of Chuck Jones cartoons with Marc Anthony and Pussyfoot, starting with Feed the Kitty, are fueled by this trope. Big, gruff bulldog Marc Anthony completely melts before adorable kitty Pussyfoot and becomes a staunch protector of the na´ve kitten. Honestly, who wouldn't?
On The Penguins Of Madagascar, the penguins were tasked with hatching an egg. Most of them don't last very long before succumbing to their brooding instinct despite their leader's insistence that they think manly thoughts. Then again, they may have been doing just that — as Kowalski points out, "incubation is a guy thing for penguins". Cuteness Proximity comes up again in the episode "Cute-astrophe", when Private discovers how to turn his own cuteness up to 132%, which makes people faint on sight.
On The Venture Brothers, a lot of cats pounce on Dr. Orpheus in one episode, leading him to giggle and say "They smell my cat!"
Ugly Americans. A werewolf was on trial for tearing a man's arm off, and there was very clear evidence of what he did. The werewolf had a giant baby as a lawyer though, who's only defense was taking a giant bowl of spaghetti and dumping it on his head like a baby does. The judge thought it was adorable and dismissed the charges.
It is a weakness of Word Girl in one episode, in which a villain called "The Butcher" (who is just a guy obsessed with meat) owns a kitten and discover that whenever WordGirl gets close to the cute kitty, she gets distracted. Justified since that WordGirl is a little girl.
Weaponized by the natives of Thuban 9, or as we call them, housecats. They intentionally utilize cuteness proximity to control the minds of the cast.
When someone devolves into baby talk around Nibblonians they tend to get rather irritated, though if Nibbler is any clue some actually develop a taste for that kind of treatment.
The mission to get honey from Space Bees in the episode "The Sting" would have gone without a hitch, had Leela not seen that baby queen bee and decided to take it with her (she had a good reason to, however).
On Jimmy Two Shoes, this happens to Twinkles, a unicorn, to the point where even Heloise is effected. Tha catch is that Twinkles is an Omnicidal Maniac that makes repeated threats that no one takes seriously, until he finally gives up and leaves.
In her introductory scene in My Little Pony: Friendship Is Magic, Fluttershy is a complete Shrinking Violet, her attempts to introduce herself growing more squeaky and whispered when Twilight Sparkle tries to press her for her name. That is until she catches sight of Twilight's baby dragon Spike. She opens up immediately and carries on a conversation with Spike all the way back into town, which Twilight had to interrupt once they reached her home.
As seen in the episode "Baby Cakes", Pinkie Pie's usual response to Cuteness Proximity is an urge to burst into song — even in the neonatal wing of the Ponyville hospital.
Averted by Rainbow Dash, who shows a remarkable resistance to the incredible cuteness of a cat offered to her by Fluttershy in the episode "May The Best Pet Win".
Though even she can't resist giving her Tortoise, Tank, a blink and you'll miss it nose rub before leaving on a trip.
Happens in a Freakazoid episode, only the animal is rabid. Freakazoid names him "Foamy".
Invader Zim tries to weaponize this trope by turning a hamster into a giant monster. It does work, as the military is too busy gushing to fight back... but "Ultra Peepy" won't follow Zim's commands.
The Phineas and Ferb episode "Meapless in Seattle" features "cutonium", a substance which renders the drinker hypnotically, irresistibly cute, inducing effects of this kind in anyone who sees them. When Mitch drinks it, Meap warns everyone to cover their eyes. Phineas...doesn't, and he's basically incapacitated until Isabella snaps him out of it.
Phineas: Aww! They're blasting away at each other with really cute death rays!
On The X Factor and American Idol, Simon Cowell is seen to be affected by Cuteness Proximity. The Mean Brit is actually a vegetarian and animal lover, and his meanness fades away whenever any auditionee brings their pet dog into the audition room.
Happened again to Simon during auditions for Britain's Got Talent, when an little girl sang the most adorable rendition of "Somewhere Over the Rainbow", and he damn near cried. (It helped that the girl sang better than a lot of adults on the show.)
Whenever someone brings a dog, he usually ends up holding it in his lap. It's likely that there have been more than a few Genre Savvy contestants who have taken advantage of this.
This video of two sea otters napping. While holding hands. Judging by the cooing in the background, everyone around is in dangerously close proximity.
This is a known phenomenon in the study of linguistics. It has been termed "motherese" (among others) but is known to happen to pretty much anyone holding a baby. There is a raft of theories as to why this happens. However, there are probably some exceptions, seeing as some people find babies the opposite of cute.
Kristen Bell is usually seen as a very smart and sensible girl. She also has a serious weak spot for sloths. So much so that when her boyfriend was able to bring a sloth to her house for her birthday, she was moved to tears before she had even seen them. When she was on Ellen Degeneres's talk show, Ellen merely hinted that there was a sloth there, and it was enough to send her into tears all over again.
Whenever there's a child in a Doug Walker Q&A panel, you can be assured his normal eloquence will take a backseat to cooing over them.