They use pet names that even Fluffy the Terrible winces at, cuddle and giggle incessantly, never argue (unless you count their "you're cuter" exchanges as such) and basically turn all nearby salt into sugar. They might sometimes wear Coordinated Clothes to make sure everybody notices they belong together. Usually, they're as indestructibly upbeat as you think. Other times, the show will delight in giving them one tiny imperfection, problem, or Single-Issue Wonk that makes them turn into The Masochism Tango.
To be fair, almost all relationships go through a "Honeymoon Phase" in the first few months of dating, where the couple can do nothing but sing each other's praises, much to the annoyance of their friends, families, and coworkers (especially the single ones). But after awhile, passions cool as the couple integrates the relationship into their everyday lives. Granted, you do have those couples who never stop laying it on thick. A Sister Trope to Make-Out Kids, when a couple makes others feel uncomfortable by being very affectionate in public, and Insatiable Newlyweds, when tying the knot starts up the sugar rush all over again.
- Many fanworks have Phineas and Isabella as young examples of this trope. Here is a far from complete list
- Axis Powers Hetalia fanfic Gankona, Unnachgiebig, Unità: Let's just say once Italy asked both Germany and Japan out and Germany and Japan fell for each other, the three's relationship basically becomes this.
- Axis Powers Hetalia fanfic Cucinando
Sōkoku?: Romano actually references this trope by name after watching Italy and Japan share a kiss while eating spaghetti.
"Chigi! Your relationship is a hypersaccharine concoction of supersaturated snappiness! You guys are sickeningly sweethearts who never argue! Heck, you guys can never be on opposite sides of anything! I'm going to puke out rainbows at this rate! I'm going to get diabetes from all this!" Romano's blood sugar levels had soared through the roof, only worsening his already horrible mood. He made the worst of hyperglycemics look dangerously hypoglycemic in comparison. He may or may not have been jealousHE WAS NOT!
- The Twilight Child: While Big Macintosh and Cheerilee (see Western Animation) talk like this when afflicted by a love poison, Shining Armor and Cadence are like this naturally, all the time.
- On a Cross and Arrow: Rarity and Elusive, in their own way, as well as Fluttershy and Butterscotch, in a more awkward and shy sense.
- Scootamom: Cadence and Shining Armor, again, much to Scootaloo's disgust whenever she has to witness it.
- The Infinite Loops: Almost any Looping couple is liable to be like this. Korra and Asami, for example, who spend one Loop being nothing but this. It annoys Mako, on account of their replacing Belle and Beast (he's replacing one of the servants, and is still cursed because they haven't bothered lifting it).
- Played for Laughs in Cinderjuice and its sequels. BJ is amused to find that he enjoys pretending to be this with Lydia, because it confuses and possibly nauseates the hell out of onlookers, especially her parents. They act much more relaxed in private.
- Titania Falls: Erza and Jellal have a lot of lost time to catch up on. It's so bad that Mabel, Dipper, and Stan treat it as something to specifically avoid whenever they can.
- A running gag in Skyhold Academy Yearbook is that Cullen and Evvy are "so cute it's stupid." They admit there's some justification to the comment.
- Female Transfiguration 101: Ginny once knocks Ron off of his broom because he would not stop complaining about her and Hermione making out in public all of the time.
- Googly-Bear and Schmootzy-Poo (aka Mike and Celia) in Monsters, Inc., which leads to a moment when Celia refers to Sulley as "Sulley-Wulley" and he reacts in a combination of taking it in stride (calling her "Celia-Welia") and "What the...?"
- In Antz, Chip and Muffy (the Cultural Posturing wasps). Chip is referring to Muffy as "Cuddly Widdles" and "Wattling Kiddles".
- Barbie and Ken from Toy Story 3. Buzz makes a "you have got to be kidding me" facial expression after overhearing a conversation between them.
- The love potion from Strange Magic causes this among the various denizens, much to the disgust of the two leads.
- In The Emperor's New Groove, Pacha and Chicha deliberately invoke this trope to get their kids to go to bed.
- Winsor McCay had a couple like this in one of his early minor features.
- In Who Framed Roger Rabbit, this proves to be Jessica and Roger's relationship. "Honey-bunny!" "Oh, love cup!"
- Spoofed in the movie The Naked Gun 33 ⅓: The Final Insult. While at marriage counseling, Frank and Jane start calling each other sappy pet names. At first the therapist smiles at the display, but after a few more he says "Mr. and Mrs. Drebin, I'm a diabetic. I think you two ought to go now."
- In The Mummy Returns, whenever Evelyn and Rick kiss, they'll get a disgusted look and the "Find yourself a room" comments from their son and/or Evelyn's brother Jonathan.
- The pair of robbers (Amanda Plummer and Tim Roth) at the end and beginning of Pulp Fiction are this. They're even credited as "Pumpkin" and "Honey Bunny."
- Parodied in Chitty Chitty Bang Bang in the song "Chu Chi Face." (And you're my teddy bear. Together we're a Chu-Chi Woo-Chi, Ooo-Chi Coo-Chi Pair!) Of course, the entire time the Baron and Baroness are singing this to each other, he's trying to arrange an untimely death for her, resulting in her getting more and more nervous and uneasy as the song progresses.
- Karin and Larry Blake in Two-Faced Woman, who were all over each other when they were presumed dead by Larry's colleagues. The newlyweds don't hold back on kissing each other when they're not talking, play-fighting on the floor and talking about how happy they are. It's so sweet that, at first, Mr. Miller thinks that they're trying to distract him and Miss Ellis from making Larry go back to work.
- The Irving Berlin song "Snooky Ookums" mocks the Baby Talk manners of a pint-sized man and his 180-pound wife:
She's his jelly-elly roll,
He's her sugey-ugar bowl.
Here's the way they bill and coo:
Poogy-woo, poogy-woo, poogy-woo.
All night long he calls her
Snooky Ookums, Snooky Ookums.
All night long the neighbors shout:
"Cut it out! Cut it out! Cut it out!"
- The whole point of the song "Lucky" by Jason Mraz and Colbie Caillat. 
- Mocked in the song "Mon coeur mon amour" ("My heart my love") by French singer Anaïs.
- "Disgustingly In Love" by Mitch Benn.
- The Jamster bunny characters Snuggle and Snuggelina (Schnuffel und Schnuffelienchen in Germany) not only love eachother. But Jamster even made two songs about how much they love and care about each other. Even the art by the company featuring◊ the two is already cute enough.◊
- In Calvin and Hobbes, Hobbes tends to describe love to Calvin in terms likely to nauseate adults ("'Bitsy Pookums,' I'd say. 'Yes, Snoogy Woogy,' she'd reply..."), let alone a six-year-old inclined to believe that Girls Have Cooties.
- "Richandamy" from Zits are a high school relationship taken all the way to symbiosis. The only time the two were ever seen not hugging was one strip where Rich was using the men's room. The rest of the cast are torn between a strange admiration and incredible disbelief towards them.
- Amusingly, Richandamy were based on two college friends of creator Jim Borgman. They were actually named Rich and Amy, he was tall and she was short, and they practically were that inseparable. They're now Happily Married with three kids.
- Peter and Denise of FoxTrot were known to be like this from time to time. One occasion featured them in a rather sweet moment, in which Peter talked about how unbelievably great it was to finally have a girlfriend like her. "Just great?" she responds. "Okay, super-duper-ooper-great." "You're so cute." And of course Jason and Marcus are spying on them behind a clump of bushes, causing Jason to whisper: "If I'm ever that cute, shoot me dead."
- While they weren't "married", Jim Cornette was "close enough" with The Midnight Express for fans to start chanting "Faggot!" at him, sometimes when celebrating with them and especially when he would "cuddle" with them for protection from crossed baby faces.
- When they weren't performing some gruesome act of violence, Stevie Richards and Victoria spent most of their hugging and sweet talking each other. And yes, they had coordinated ring gear, which was usually pink.
- Despite being a Gorgeous George, the wrestling stylist Rico Constantino and his valet, Miss Jackie, were very touchy feel with one another, routinely rubbing noses before matches. (Of course, this is exactly what made the gimmick work)
- "Team Be Jealous" were as close as sisters and occasionally mistaken for lesbians. Jessicka Havok even imitated Allysin Kay's hair and fishnets.
- Mike Bennett and Maria Kanellis, two trouble makers in Adam Cole's Ring of Honor group "The Kingdom", to the point after Bennett was given Matt Hardy's "Icon Title", he renamed it the "Title Of Love". This continued when they came (or in Maria's case, came BACK) to WWE in June 2017.
- Cody Rhodes and Damien Sandow, while not "a couple" in the traditional sense, were very "Best Friends", which the latter would state at every opportunity while also talking up Cody's finer mental and physical points, especially his mustache.
- Thomas and Martha Jefferson in 1776. Tom misses Martha so much that he's rendered completely unable to concentrate on writing the Declaration of Independence and Adams has to send for her. When she arrives, she and Tom glom onto each other to the extent that they don't even notice anyone else is in the room; afterwards, Martha has a number about just how much she loves Tom and his violin. (Contrast this with John Adams and his wife Abigail, who — having been married for considerably longer — spend as much time bickering as they do flirting and sometimes do both at once. Truth in Television; one of the reasons Adams fell so deeply in love with Abigail in the first place was because she was his equal in snarkery.)
- Discussed in "Before and After" from Babes in Toyland:
Before they were married they talked like this:
"Will lovey's own dovey give love a kiss?"
"Will owney's own ownest be ever true?"
And "Oos 'ittle oozelly oose is oo?"
Ha! Ha! Ha! Ha! Pardon the laughter.
That was before but this is after!
- Benedick from Much Ado About Nothing disdains love in general, but he specifically complains that becoming promised to Hero has turned Claudio soft.
I have known when he would hear no music but the drum and the fife, now he would rather hear the taber and the pipe.
- Abbey and Daisy from Bittersweet Candy Bowl.
- In The Order of the Stick, this proved to be Therkla the half-orc's backstory. Stereotypically half-orcs are the product of rape.
- xkcd: "No one must know" that Black Hat (A self-described "Classhole") and his equally terrible girlfriend Danish are like this.
- Same goes for two normally jerky classmates in Gunnerkrigg Court, minus the murder.
- Tedd and Grace from El Goonish Shive.
- Ezekeil and Ariel in Sin Fest, pictured above.
- Slightly Damned has set a new bar for this trope with Buwaro and Kieri.
- Lampshaded and played for laughs in Our Little Adventure. Julie and Lenny go out on a date during their downtime and behave this way. The Elf waiter who is serving them seems to be reacting how the audience would.
- Parodied in Questionable Content, when Marten and Dora engage in cutesy banter...about necrophilia.
"At least they're not one of those sickeningly cute couples. Just sickening."
- Parodied to Hell and back in Sire, where a die-hard Edgar Allen Poe die-hard fan / descendant / supernatural roleplayer finds her mister charming... and then tries to ruin his life according to The House of Woe's script, and fails because her boyfriend is too thick-headed to start growing terrified of love AND he's as creepy as her so she can't even hate him for it.
Delores: I'm the real victim, here!Susan: So, um, you? Not the man you're going to emotionally scar[?] After helping all your friends kill themselves, and, effectively, their innocent boy-toys, you were going peak murder-boner over this guy. I mean, you're the boss. This was gonna be your group's masterpiece. [...] You're in a [romantic comedy], Delores.Delores: AAAAAAAAA
- Cho and Cedric acting like this in A Very Potter Musical piss Harry off to no end since he has a crush on Cho. It actually doesn't end well though since Cedric gets murdered.
- The Lizzie Bennet Diaries: Jane Bennet and Bing Lee when they start dating. She bakes him homemade cookies. He watches romantic period drama with her and treats her like a princess, pretending to carpool when he in fact just keeps giving her a lift. Lizzie is happy for them, but she implies that sometimes they're too much to take and also that Jane has the "I-want-you-to-be-in-a-happy-relationship-like-myself" vibes which make her uncomfortable.
- Barbie: Life in the Dreamhouse portrays Barbie and Ken like this. For starters, the first episode begins with Barbie getting ready to celebrate the 43rd anniversary of the first time they held hands, even revealing that she made Ken a card after failing to find one at the store.
- Due to the No Hugging, No Kissing tendency in Noob the relationship between Arthéon and Kary gets depicted this way until the Season 4 finale.
- Would you believe a pair of boats can be this? SCP-1522 is a pair of Sapient Ships that follow and play with whale pods, 'kiss' by gently nudging into each other, and 'talk' to each other using their foghorns. Word of God is that the foghorn conversation between the two transcribed in the log consists of "I love you" and "I love you too." Unfortunately, it ends tragically.
- One of Thomas Sanders' Vines is set up around this, ending with him carrying the girl down the hall ballet-style with an "I'm off to class with my lady love!"
- There's always at least one showmance like this in a theatre production. To everyone involved, it's a distraction.
- This trope can be particularly annoying if you're single yourself and your go-to single friend and partner in crime has just seemingly found the person of their dreams. Hell, it can be downright lonely and depressing in that situation. If that's you, don't worry; eventually your friend will come back around once the relationship stabilizes (assuming they don't break up; love can be fickle).
- Subverted in the Behind The Music episode about TLC. When Left Eye was dating football player Andre Rison, her bandmates would get annoyed by their sappiness. T-Boz mentioned how they'd always call each other baby: "Hey Baby... Baby... Baby..." and it segued straight to Chilli, interviewed separately, saying the exact same thing. Two years into the relationship Left Eye burned his house downnote when she thought he was cheating.
- This installment of Gothic Charm School provides some useful tips for dealing with people like this.
- Lovebirds are famous for essentially being the Sickeningly Sweethearts of the bird world, to the point that an Urban Legend has it that a lovebird will die of loneliness if kept without a matenote . Needless to say, the urban legend coupled with the adorableness of these birds cuddling and preening each other is often what leads potential lovebird owners to always buy two of them...only for them to be baffled when they realize that the birds refuse to pay any attention to them because they're so wrapped up in each other.
- Subverted on Facebook by the dreaded joint profile: "JohnAndMary Parker" for instance. The couple wants you to think they're perfect happy lovebirds, but it's far more likely that someone got caught cheating. The real purpose of these accounts is so that both partners have full access to chat history.