This cartoon set the bar for a lot of 1990s and 21st century kids' cartoons that don't want to adhere to the unwritten rule that cartoons are for kids, though, looking at most of these examples, the bar may have been set a little too high — at least by Nickelodeon's standards. If this were a Cartoon Network show, only 40% of the dodgy content actually would be a problem with the censors.
The episode "Nurse Stimpy" appears as one huge Unusual Euphemism for various homosexual practices. Some evidence includes:
The disturbingly numerous times Stimpy has asked Ren to open his mouth with a mischeviously enthusiastic expression,
The "tools" he displays for performing the tests,
The hilariously and suggestively exaggerated spoon scene with Double Entendres like "Now swallow every little drop! Isn't it tasty?" and "This is some icky tasting-stuff!" (the latter line would have been less dirty if Ren specified that it was medicine) note The spoon is brought up again in "Fake Dad", in which Ren feels it's necessary to inform us that "he has some tasty icing on his spoon"...
The sponge bath sequence. ALL. OF. IT. Not only does Ren initially have a negative attitude about it and get extremely defensive about "taking off his fur", insisting on doing it by himself, but after a while he also eventually starts enjoying it. The Ho Yay page that lists this cartoon episode describes the sequence as having the same parallels as a straight, yet bi-curious man "giving into the moment" with a gay man (and the Double Entendres here don't disprove that theory either: "You know, this is not so bad. In fact, I feel better already. You're so good to me, Stimpy. It is embarrassing, though"). The kicker comes when the shocked/amused bystanders (one of which includes that horse who sometimes appears on the show) in the window are exposed to us, and the scene after that, where Ren relapses after reading that the bath made headline news ("Ren Hoek Takes Bubbly Sponge Bath").
"The Royal Canadian Kilted Yaksmen": The titular anthem features the word "hell" censored with an appropriate fart...quite poorly. In fact, thanks to Carbunkle's attention to specific mouth movements, you can still see Ren and Stimpy mouth the word "hell".
"Son of Stimpy", obviously. It features Ren acting pretty desperate for a change - Stimpy is standing at the door, calling for his son Stinky. It isn't before Ren points up at the mistletoe hanging over the door, bites his lip and coyly bats his eyelashes, that causes Stimpy to shout at him "THAT'S ALL YOU CAN THINK OF!"
Also in "Son of Stimpy" when Stimpy is searching for his lost fart he encounters a store Santa, it shows him ringing a bell for charity donations and he says "Ho Ho Whoa!" with a shocked look on his face and he frighteningly turns around to see Stimpy sniffing his butt.
There has been generally plenty of kissing between the two throughout the series, including a completely direct one in "Big House Blues" (with Ren unaware of the person he's smooching). The Accidental Kiss on "Big House Blues" was cut when it premiered on Nickelodeon (despite having the scene of Ren rushing to the toilet to clean out his mouth in the opening sequence), but was finally shown when Spike TV aired the show.
"The Great Outdoors" is another one with plenty of Accidental Innuendo (whether or not it can truly be considered "accidental" is up for debate).
When the same guy starts running towards the lake, We cut to Ren and Stimpy and see their pupils bouncing up and down, suggesting a certain kind of "jiggle physics"
When Stimpy asks Ren to light the fire:
Ren: Whaaat? Do I have to do everything around here?
Stimpy: You know I'm lost without you.
Somehow, that seems to have convinced him.
Not to mention that when Stimpy comes back, it's with a flower garland on his head and skipping in an utterly queer manner.
Stimpy has played the role of Ren's housewife several times, in "Fake Dad" or "Ren's Pecs" for instance.
In "Haunted House", when, naturally, Ren and Stimpy go to sleep together and Ren cuddles up to Stimpy, he notices his stench and immediately sends him to take a shower. While Stimpy does that, Ren suddenly pops in the door, not feeling uncomfortable at all for entering in the middle of Stimpy's shower, but he also reminds Stimpy not to "forget to wash where the sun don't shiiine!" much too cheerfully to let this line slip.
"Sven Hoek" has some questionable moments with Stimpy and Sven. When they're playing hide and seek, or as said in the episode, seek and hide, Stimpy hides in a closet. After Sven finds him, they both sit in Stimpy's rather unimpressively sized litterbox. After a minute of blabbering, Stimpy realizes something and scolds the "cameraman", "Hey! This is private!", closing the closet door afterwards.
That scene was cut in reruns recently on Nicktoons.
The original version of the episode had a longer version of this scene that was cut in every airing, and was only seen in bootleg versions until it was restored on the DVD release. Sven and Stimpy are heard playing "circus": "I'm a juggler!" "I'm a bearded lady!" "And I'm a sword swallower!"
My dinosaur droppings...PAINTED LIKE EASTER EGGS!!!!!
Fair amounts of blood can be seen in a few episodes. "Sven Hoek" has Ren imitating (albeit very realistically) "tearing [Stimpy and Sven's] arms out of the sockets" - while he does that, a spray of blood is visible for a brief moment. In "The Royal Canadian Kilted Yaksmen", at the end of the song while hats are being thrown into the air, there's a very indiscreet shot of a bleeding intestine flying among the head gear. (complete with a turd flying off the screen) In "The Great Outdoors", Ren smashes an already fed mosquito that landed on his arm, which leaves a pretty nasty bloody stain. During the surgery in "Ren's Pecs", a very generous spray of blood appeared, along with some heavily bloodstained bandages.
The very first broadcast episode "Stimpy's Big Day" has Ren angry at Stimpy for entering the jingle contest over his objections. Later, as they're both at opposite ends of the same bed, a contrite-looking Ren haltingly starts to apologize...nope, not at all like an old married couple, nope.
In "A Yard Too Far" the duo have to get past a baboon, who is guarding some hog jowls that they want to eat. Near the end, Ren uses a female baboon puppet (who happens to look like Judy Jetson). The baboon falls in love with it and demands they get married. Later, the baboon takes the puppet with Ren's hand still attached and takes it inside his house, hanging a "Do not disturb" sign on the door. We hear the baboon happily grunting and Ren shivering in disgust.
In "Farm Hands", at one point Ren is hired to milk a gorilla named Bossy. He doesn't want to do it, and gets Stimpy do it for him. During the process as you can hear the gorilla happily grunting while it rubs Stimpy's head, and he remarks "Hey Ren, I think Bossy likes it, I like it too" and he drinks some of the "milk" and points out how funny it tastes.
Also, in that same episode, at one point, while Ren is having spasms as Abner and Ewalt use him as a foot stool, he appears to be flipping them off with both fingers.
"For I have a dream that one day, everyone... everywhere... will know the wonders of my nipples!"
For clarity, that was the episode where they were door-to-door rubber nipple salesmen. No, it does not make any more sense in context; yes, it WAS done simply to fill an episode with nipple references.
Whatever Mr. Horse was probably doing to the walrus that would make him whisper, "Call the police!"
On that note, when they went to go sell nipples to the couple, Ren explicitly mentions that they make good hickies.
In "It's A Dog's Life" their new owner Granny Cartwright feeds them very old hardened dog food, Stimpy starts choking on his and Ren performs the Heimlich Maneuver, at that moment Granny Carthwright walks in sees this thinking they were doing something else and says "Good Lord, stop that!" and sprays them with a hose and says "You should be ashamed of yourselves, and on a Sunday too!"
To drive the point home, in the very next scene, they're on the way to the vet to be neutered.
In "Fake Dad" Ren has finally had enough of Kowalski's bad behavior so he decides to spank him with a giant spoon, once he pulls his pants down Ren has a surprised then shocked look, he then starts crying and tells Kowalski to pull them back up.
Kowalski is also reading (or attempting to) one of Ren's books called "Prison Love".
Plus, Stimpy tells Ren to "be nice to the product of your loins"
In "I Was a Teenage Stimpy" near the beginning when Stimpy is going through puberty it is strongly implied that Ren thinks that Stimpy is masturbating in the bathroom and Ren's "Husk" magazine for the adult corn lover, later when Stimpy opens the magazine a page unfolds like a centerfold model.
In "Prehistoric Stimpy" when Wilbur Cobb shows off the dinosaur fossils one of them is labeled "Homo Gigantis Erectus", and the kids who are part of the tour group have very shocked reactions to it.
In "Powdered Toast Man" the joke of the President getting caught in his zipper while kneeling in pain over a toilet, if you've seen "There's Something About Mary" you might know what's happening here.
Also, the visual innuendo of Powdered Toast Man roasting a weenie and PTM's lovely assistant roasting a melted marshmallow during the romantic ending.
In a stark contrast of what Nickelodeon censors deem is appropriate compared to what isn't, the reruns of this episode cut the part where Powdered Toast Man uses the Bill of Rights and Declaration of Independence as kindling for the fire and all appearances of The Pope (who was voiced by Frank Zappa).
In "A Scooter For Yaksmas" look carefully at Stimpy's Stinky Wizzleteats clock, he has a big smile on his face with shifty eyes and he has two pink pendulums hanging from his crotch area.
In "The House of Next Tuesday," Ren and Stimpy share a bed that expands when exposed to moisture. During the night, Stimpy smiles and makes pleasurable noises, after which the bed violently expands. Stimpy may have wet the bed (as in "peed in it"), but his smile and noises suggests that he may have wet the bed in a sexual way.
In "Big Flakes," Stimpy tells Ren, "It sure was nice of your parents to loan us their cabin for the weekend." Stimpy does so with a big smile and a suggestive glance.
In a scene towards the beginning of "Hard Day's Luck", if you look closely at the cereal box, the cereal's name is Lucky Chodes (a "chode" is yet another slang term for a penis).
Think that's bad? The Billy the Beef Tallow Boy commercial opens with a father telling her daughter to PLAY with her Lucky Chodes.
In an episode that never was, called "Wilderness Adventure", George Liquor is hunting ducks, so he disguises Ren as one, and plays a duck call. A duck instantly sees Ren and falls in love with him. He performs some bizarre ritual where he chews a couple of fish and regurgitate them into his mouth, and then proposes to Ren. All topped off with Stimpy saying "Isn't love grand?"
There is a disturbing amount of literal examples in this show (especially in the Games episodes), where characters quite clearly say the word "crap" onscreen. In particular "Prehistoric Stimpy" and "Weiner Barons", where it's said MANY times.