The larger the penis, the better the sex.
This assumption is a staple of modern fiction when it comes to Sex Tropes. It's the reason why Compensating for Something is, by its very nature, an insult — everybody knows that a real man has a big penis. A heroic character, when his penis is mentioned (which isn't all that often, except by innuendo), will usually have a big one.
Consequently, this is also the reason why villainous or loser characters are portrayed as having a small penis, or a small something else meant to represent a penis. It's a deficiency that makes them bad people, or at least not cool like the heroes are. By further extension, Good People Have Good Sex, to some degree because they're usually well-endowed.
Also expect many authors to give us the exact dimensions of this uberpenis, conjuring the mental image of a PoV-character breaking out the measuring tape.
Unsurprisingly, most writers don't really think through the Real Life implications of this. First, regardless of personal preferences, if someone's penis is too big for their partner's orifices, intercourse could be physically painful, if not outright impossible. Second, this trope makes the assumption that penetration is all there is to sex, which displays a failure of imagination as well as ignorance of how sex works — only about a quarter of women, for example, are able to climax from vaginal intercourse alone, regardless of their partner's size. So there's something to be said for technique over endowment.
When a large penis has comedic value instead of sexual value, see Gag Penis. Contrast with Teeny Weenie, which is a penis which is smaller than the average, and often leads to mockery of the guy who has it because of this trope. The female equivalents for this trope are Buxom Is Better or Gag Boobs. Often related to IKEA Erotica, and when taken to extremes can become a case of Anatomically Impossible Sex, or alternately of Writers Cannot Do Math.
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There's a late-night infomercial for a penis-enlargement pill with "testimonials", and among them is a woman who calmly states that the biggest penis she has ever been with was "ten or eleven inches" like it was no big deal, acting pretty calm about the fact she most likely had sex with a small pony, a large dog, or a very abnormal man.
"Over 88% of women say that size DOES matter. And the other 12% are lying."- Opening line from 'Extamax' commercial. It later uses the Empire State Building, and pictures labeled 'actual disappointment' and 'actual hopelessness'.
Spam for penis-enlargement pills. Perhaps most notable, not to mention worrying, was the spammer who sent out e-mails with the subject line: "12 more inches ain't so bad, don't you think so?". 12more inches?
Roberto from Monster. If we are to believe the obese prostitute with whom he was having sex.
Panty from Panty & Stocking with Garterbelt certainly believes this, but this trope is actually subverted when she tries to have sex with Brief after she regrows her hymen in the final episode — his size just makes it even more painful.
Averted in Koibana Onsen, Shuuhei's large penis makes it even harder for him to get intimate with his girlfriend who has anxiety problems.
Several characters in the Italian porn series Ramba. Deconstructed; it is shown as being painful to the women involved, and is sometimes used to deliberately torture them.
In the Love And Rockets "Palomar" stories, Gato, who has been married to both Pipo and Guadalupe, has a huge one. Pipo has apparently become accustomed to it and doesn't think much of average-sized men. She dates Igor, of comparable size (Gato and Igor actually compare in a bathroom), and later has several sexual encounters with an unnamed, sleazy-looking character who dwarfs even Gato and Igor. She has no problem with his size in any opening. But then there's Fritzi, who has a fulfilling sex life with mostly average-sized men - ironically including Pipo's son Sergio - and is twice married to the "love of her life," Scott the Hog. He's described as having a barely functioning "choad."
Exaggerated, parodied and deconstructed: inspector Maccaroni sports a 40 cm thing. He's shown having a first time with a rentboy, who thinks he cannot handle it despite his profession. Maccaroni claims that "they all whine like that in the beginning, but in the end, they all love it". However, Maccaroni is unhappy because he feels that his lovers only love his penis and think they tend to forget that "there's a person hanging from it".
Discussed: Maccaroni meets a similarly well-endowed porn actor, and they have a talk about how very large penises can be troublesome.
Shows up again in another Kalash93 story called "Relax." It's implied that not only does the protagonist not have a prodigious endowment, but that the sex is actually better for it. This is an example of Truth in Television. Average and somewhat smaller are actually the most ideal penis sizes because they can be easily and comfortably accommodated by women of varying sizes and equipment.
The fanfic version of this trope, taken to its logical extreme. (The link doesn't go to the fic itself, just the fanfic-rants post about it. The fic itself, unfortunately, is lost.)
valorously: That's bigger than some children. IT COULD GET ON DISNEYLAND ATTRACTIONS BY ITSELF.
Trevor "Hotshot" Cole of DC Nation had a brief stint as a porn actor. When this is discovered, his female teammates and their friends track down the film and make a movie night of it. Batwoman (Kathy Duquense from DCAU) is notably impressed at Trevor's "door prize from God".
Actually played for drama in Misfiled Dreams, about how it being too big might not actually be pleasing for a woman, but rather painful.
Inverted in A Chinese Torture Chamber Story, where it's also a plot point: Gott has such an impossibly large penis that no woman will have sex with him. He's also a very nice guy, so he refuses to force his arranged wife to take it. Eventually, the size of his genitals and what happens to them are the single most important plot point. This movie is weird.
Inverted in Full Metal Jacket, where a Vietnamese hooker doesn't want to have sex with a black Marine, because she thinks that his penis is too big. He demonstrates that it isn't.
Lady Snowblood averts this. When the blackmailer Genjiro reveals his gigantic penis, the reaction from Oyuki, the title character, is not adulation, but horror. Genjiro himself is aware of the implications of his large penis, noting that one that large will usually cause the receiving woman serious pain. (In the manga it was made clear that Oyuki was a lesbian.)
Aversion: In the film Kinsey Alfred Kinsey and his wife have come to a doctor because they're having trouble consummating their marriage. The doctor explains that sometimes, if a woman with a thicker-than-usual hymen is matched with a well-endowed man, it can make sex tough. He holds out a (short, roughly 6") ruler and asks Kinsey's wife to point to the ruler, indicating how big the... member in question is. She hesitates, then points to a spot in the air TWO INCHES past the end of the ruler. The doctor just raises his eyebrows a bit and says, "I'm surprised you didn't pass out."
The main character in The Seventies film Welcome Home Brother Charles kills his enemies and pleasures their wives with his ridiculously large and prehensile penis. And of course, it's Blaxploitation.
Dirk Diggler in Boogie Nights. His very large penis is the main reason he got into the porn business. Dirk was based on the real-life porn star John Holmes, who was famous for the same reason.
Discussed in the German movie Der Eisbär. The titular character worries a bit if he's "inadequate". A female friend of his ex tells him that it's not length that matters, but girth. He shares that information with others later.
Dashiki: Oh, so you're man enough to come up in me, but you ain't man enough to take care of what comes out, get my nails done, pay my rent, and get me a new car? You know what? You ain't nothing but a little boy.
Ashtray: Ain't all about the size of the boat! It's the motion in the ocean.
Dashiki: ...That's not what I'm talking about.
In Legally Blonde, a woman named Brooke is accused of not just killing her much older husband, but of being a Gold Digger. She points out that she didn't need the dude's money as she's already wealthy... and insists that her husband had other assets of interest, thank you very much. Three guesses as to what.
Showdown in Little Tokyo. According to Murata, Kenner has "the biggest dick I've ever seen," said with a complimentary tone. Unsurprisingly, he's portrayed as a sexual dynamo.
This is standard procedure for romance novel heroes.
Averted with sex blogger Abby Lee in her memoir Girl With A One Track Mind. Abby has lovers of different penis sizes and doesn't believe it makes a difference to the quality of the sex
Played seriously in Harlan Ellison's short story "I Have No Mouth and I Must Scream", in which one of the main characters, Benny (a formerly gay and very handsome scientist), is transformed by AM into a apelike creature with horse-like genitalia. This may be Values Dissonance and/or Unfortunate Implications in action, as gay men can be as fond of this trope as straights (see, for example, the work of Tom of Finland); Ellison implies that AM made Benny ugly and partially retarded because he was handsome and smart, and that making him over-endowed was to make him appealing to the one woman trapped in AM.
After her first session with a new love interest, the heroine of Steel Beach specifically references this trope when she bitches at length about the tendency of first time Female-to-Male gender benders to check off the "HUNG" option even though they'd just been girls themselves and really ought to know better.
Also averted in Varley's Titan series, when a woman from a monogender Lady Land informs her first male lover in all seriousness that she's very happy his penis isn't too big - she's been told that all men are constantly raping women (often to death) with their enormous penises. The first time she sees one, she actually giggles, because she can't believe that's what she's been warned about. He takes it as a compliment anyway.
She also discovers early on that a Titanide's "rear" penis matches the horror stories much better, but while intimate relationships between humans and Titanides canonically do happen that again just serves to point out that it's just not practical for them to have straight-up intercourse that way.
In David Drake's Cross the Stars, Don "Mad Dog" Slade dismisses the notion that a large penis equals sexual prowess ("It's not the size of the tool, it's the skill of the workman") but not until after the author mentions that his army buddies briefly called him "Tripod" before an earlier nickname reasserted itself.
Deconstructed in the Earth's Children series. Jondalar spends much of Valley Of The HorsesWangsting about how he can't find a woman who can take him at full length without pain, despite his otherwise legendary bed skills. The fact that Ayla could is one of the things that supposedly mark them as soul mates. Never mind that those who'd read the first book, Clan of The Cave Bear, know there's probably a not-so-wonderful reason Ayla can take him without complaint. His defining trait earned him the nicknames, "Jondalar The Wonder Penis" and "Dongalar."
Mario Puzo takes a rather large detour from describing the Corleone family saga in The Godfather to describe Sonny's large penis. The moment makes it into the movie as well if you're looking for it during the wedding scene - watch his wife's hand gestures carefully. However, this is one of the few realistic examples: His wife complains how painful sex is, and Sonny's mistress Lucy has an enlarged vagina. Lucy needs vaginal reduction surgery later on, in order to have good sex with lesser men than Sonny.
There is an Arabian Nights-inspired story in which two illicit lovers earn a single wish each at the story's beginning. The hero uses his one wish for the obvious type of self-improvement, allowing him to better please his lover: a genie's human betrothed. When the genie and her father come to kill her lover, the bride-to-be uses a magical bag to reduce the hero's penis to near-microscopic size. Seeing this, the genie is so humiliated to have lost his bride to such a poorly-endowed man that he departs in shame. Disgusted, the father disowns his daughter, leaving her to whatever feeble pleasure she might gain from wedding the ill-equipped hero... not realizing that she has one wish left.
In one of Pu Songling's fairy tales, the protagonist is too well endowed for any (human) woman to handle safely. So then a Kitsune tries to seduce him, he is overjoyed. Alas, he proves too big even for the shapeshifting fox, and the narrator quips about how chasing away werefoxes could become his profession.
Mocked in one of the Deathlands novels; Doc Tanner's sometime girlfriend Lori runs off and has an affair with a local bad boy. She then returns to the group, complaining that his big dick came with a small brain. Ryan dryly remarks that he "hears that's often the way".
In the Red Dwarf novel Better Than Life, in the Better Than Life simulation, Rimmer tries to invoke this trope by acquiring artificial bodies with bigger and bigger penises, to the point where they approach Gag Penis levels. Unfortunately, instead of improving his sex life, it simply reveal Rimmer's huge insecurities, a point he is forced to confront himself over when he sees Lister's humble but happy life.
There is a Russian poem (traditionally attributed to Ivan Barkov, although the only thing experts agree upon is that it's not the case) called "Luka Mudischev". It is a story about a widow who looked for a really big dick, and found a 35 cm one attached to the eponymous guy (his last name meaning something akin to "Big Balls")... Let's just say that the end is TRULY ghastly.
In The Hellfire Club by Peter Straub, the villain Serial Killer Dick Dart is repeatedly stated to have this. He's awfully proud of it, too, saying that his name was rather appropriate. He claims that women are crazy about him because of it, and he's shown to get very frustrated when he can't make Nora climax.
In John Ringo's There will be Dragons, a small (4'1'') elf says she used to be married to a yeti. When asked why, she says, "Think about how big his hands are. Now think lower." The stunned audience goes, "Wha ... how... ?" and she replies "Everyone's the same height lying down."
Two of Tom Reamy's works of fiction (a short story and a novel) featured women raped to death (torn apart) by ridiculously well-endowed humanoid monsters (a demon and a minotaur). In one, the investigating detective measures out some massive amount of seminal fluid during the autopsy. Tom wrote well but he may have had issues of some sort.
In One Hundred Years of Solitude Aureliano Babilonia is well endowed. With him, sometimes the trope's Played for Laughs (like when he gets drunk with his friends and uses his wang for tricks), sometimes averted (his sex scene with his friend Nigromanta, in which his size scared her at first), and sometimes played straight (his sex life with his unknown aunt Amaranta Ursula).
José Arcadio was also very well endowed, to the point that it is the reason why he runs off with the gypsies.
Deconstructed in one of the Montgomery Chronicles books by Jude Deveraux: a minor character has a huge penis, but has a lousy sex life because not even the most experienced professionals will want to risk themselves handling that. Being given for him to rape is used as a sadistic threat against the female protagonist.
Subverted in Fool by Christopher Moore. The main character's apprentice, Drool, sports a Gag Penis. Several women comment that they wouldn't shag him even if he wasn't mentally retarded, as they wouldn't be able to sit down for a week. The only woman who can ride Drool without any problems is a ghost.
On the other hand, Drool, despite being dangerously retarded, IS considered great in bed when a woman finally lays with him. The ghost (who rode him and did all the work) spends most of the book chasing Drool, and the two women tricked into sex with him love it, even if they are sore afterwards. So it's more a Double Subversion.
Deconstructed in Graham Swift's Waterland. One character's too big for sex.
Mentioned in the Men at Arms, about dwarves. It's never confirmed whether it's true or not and the only (nonhuman) dwarf that asks about it keeps mistaking it for being well endowed with money.
Deconstructed in the 13th century Brennu-Njáls saga. Although this is bowdlerised in some translations, the exact nature of the curse that the Norwegian Queen Mother places on Hrútr Herjólfsson is that he becomes so large when sexually aroused that it is impossible for him to have intercourse with his wife. This ends in a divorce.
The subject of Robert Burns' "Nine Inch Will Please A Lady."
Zigzagged in It; during the sewer sex scene, Beverly finds that Ben is the most well-equipped of the Losers Club. It's very painful for her at first, but he also gives her her first orgasm.
A rare villainous (protagonist) example from L. Ron Hubbard's Mission Earth: after some extreme nonconsensual BDSM torture sessions, alien spy Soltan Gris is given enhanced equipment by a well-meaning but perverted doctor. When he goes back and rapes the women who abused him so, his oversized penis not only makes them forgive him and beg for more sex afterward, it also cures them of their lesbianism (since of course they couldn't properly enjoy sex without a man's involvement), and leads them to invite all their lesbian friends to be cured by his penis. The author also takes the trope further by emphasizing how not only does Gris' new size make sex better, but also the volume of his ejaculate.
Coupling's Patrick Maitlan had a sex toy molded after him coming in at about ten inches.
Subverted in an episode where Samantha hooks up with a guy who warns her that he has an enormous penis. She is excited at first... until she sees it. When they do have sex, it turns out that it's too huge for her to take.
In another, she meets a man who is the model for the second-most successful sex toy in the United States (#1 in Canada). It turns out that he's tired of women only seeing him as a walking penis, and tries to impress her with his poetry. She's not interested in his poetry.
Played straight in another, when she is in a steady relationship with a guy whose "equipment" isn't up to her standards, so the relationship ends up being very chaste. She tells her friends both of them have reached an unspoken agreement: he doesn't complain about the lack of sex, and she doesn't mention his below-average penis. Naturally, this turns out not to be the case. He takes her to a couple's counselor, where Samantha finally spits out her problem with him. The guy gets offended and leaves, while she just shrugs.
In an episode of Rome, Atia sends Servilia the gift of a slave with a gigantic dick. Yes, we see all of it.
Atia: A large penis is always welcome.
The MTV series The Hard Times of RJ Berger focuses on the class punching bag. One day, he gets pantsed during an assembly, and his underwear falls down in the process, granting the whole school an eyeful of his large dick. Suddenly, his social life changes radically.
Averted in the J-drama Trick. Physics professor Ueda Jiro's oversized penis is frequently commented on, and although it once impressed another man, when it comes to women, it renders Ueda a virginal loser and the butt of jokes.
The fundamental premise of Hung is that the main character, being, well, hung (and thus being well hung), can get work as a high-class gigolo.
On Friends, Rachel finds Chandler naked and handcuffed in her boss' office, although the audience sees him in tighty whities. In any event, she needs him to stay there so her boss won't know she broke in. She bribes him by promising to be complementary in her description, making him a legend and "this generation's Milton Berle." The legend lasts all of two hours.
Luckily for Chandler, when he and Monica get together she's genuinely impressed, nicknaming him "Mr Big" and certainly doing something with a tape measure. Previously it was implied Chandler was average in that department, meaning he may not be the biggest but clearly the size that pleased Monica.
In a sketch of the Saturday Night Live episode hosted by Susan Dey, she plays a judge in a courtroom scene where the defendant is supposedly well-endowed. Since this fact was important to the case, he is required to expose himself to the judge and jury. With the camera trained on Dey, the lawyers and the jury box, there is the sound of the defendant's fly being unzipped followed by the sound of his member hitting the table with a loud thump.
Implied in an episode of My Wife and Kids. Jaye paints a picture of her husband Michael in the style of Michelangelo's David; when it's unveiled at the art gallery, a woman gasps "Lordy, how do you find time to paint?!"
Rose from the Golden Girls was taught that the difference between boys and girls by her mother showing her a bull on the farm, which gave her a false impression about men and a surprise on her wedding night.
Chris: I've thought about it a lot, there's no logical explanation.
In one episode, Jerry goes to the doctor to get checked for mumps. The doctor has this to say afterwords:
Dr. Harris: That man has the largest penis I have ever seen. I don't even know if he has the mumps, forgot to check, I was distracted... by the largest penis I have ever seen.
On Bones, in the Season 2 episode "Man in the Mansion," Brennan sleeps with Sully for the first time, and comes to work the next day looking VERY happy. It turns out that Sully's nickname 'Peanut' is in the grand tradition of nicknames like calling the big man Tiny... to the point where Sully doesn't even SHOWER with the other guys, presumably not to embarrass them.
Brennan: He's statistically outside the morphological norm.
Hilariously deconstructed with an experimental 'penis enlargement spray' in an episode of the show Testies, the character's penis becomes so large that merely getting an erection causes him to pass out from hypovolemia and he has to get a transfusion to make love.
In a third-season episode of How I Met Your Mother, Robin returns from a vacation in Argentina with a new boyfriend. Ted, who still has feelings for Robin, begins to feel jealous because Robin's new boyfriend is both handsome and charming. However, when Robin tells Ted that he's got a bigger penis than her new boyfriend, Ted is elated and immediately stops feeling inferior to the new guy.
This becomes Hilarious in Hindsight given the guy who played the new boyfriend (Enrique Iglesias) repeatedly making comments about his lack of endowment years after that episode was aired.
In the Sirens US episode "Rachel McAdams Topless", when Manly Gay Hank sees Billy naked, he compliments Billy on his enormous penis (describing it as bigger than a horse's) and proceeds to hit on him.
A later season episode of Just Shoot Me! reveals that series chew toy Finch, despite being short and scrawny, is apparently very well equipped. He just didnt realize it, because his short stature meant he spent his entire life avoiding any situation where public nudity would be required such as communal showers or locker rooms, and just assumed that any mentions from the women he dated was just what all women said to their hookups. His only exposure to dicks other than his own was apparently from porn, which made him think he was about average.
Similar to the above example, Neil from Men At Work is revealed to be well endowed when a woman he hooks up with after his long time girlfriend dumps him refuses to have sex with him. At first the other guys think its because he's too small, until Neil mentions that he cant find condoms that fit. Turns out said girl was too intimidated and didnt think she'd be able to take it all in, and that his previous girlfriend took some time to get used to his size. The other guys immediatly designate him the new alpha male of the group.
Parodied in an episode of Son Of The Beach, where The Ahnold is shown to have a massive censor bar, while the main character whom everyone plays up as a magnificent male specimen despite being pasty and pudgy is shown to have a censorbar about the size of a french fry.
In Mc Chris's album Dungeon Master of Ceremonies, there is a skit where this is Lamp Shaded (so to speak). MC Chris learns that Jesus has a 4-foot penis, and asks if it hurts the women he has sex with. Jesus responds that he "magically extends their cervix up to about their chest area".
When the ladies see the beast I got between my thighs They say "Perhaps today is a good day to die"
Then, there's Rodney Carrington's song, "12 inch dick, a dozen roses and a pickup truck." The song is a man singing about the three things he has that are going to make his woman happy tonight.
Amateur Transplants' "Titanic" subverts it:
Suddenly you panic, my dick is titanic, you know it won't fit, it's too long You scream, you're sick, it's eight inches thick, and we try but it all goes so wrong...
The appropriately named Ivor Biggun sings many songs about the attractiveness of men with large penises. "John Thomas Allcock" stands out by disclosing the dimensions of the member in question. The eponymous John is described as having a penis that measured 4 feet 6 inchesflaccid and consequently being irresistible to women.
The unrated version of the music video of Robin Thicke's song "Blurred Lines" features a topless blonde woman dancing in front of the words "Robin Thicke has a big dick". It's just about the most subtle thing in the video. Later, his wife (model Paula Patton) actually confirmed it.
Pansy Division: Take a lucky guess what the song "Dick of Death" is about. I dare ya.
Scott Steiner was well known for bragging about the size of his penis, and judging by all the women that followed him around, it did mean he was skilled in the sex department.
Val Venis always bragged about his penis and his skills in bed, which seemed to be true given the amount of semi-naked women that he usually hanged out with. There was also the fact that his in-ring character was supposed to be a porn star.
In Dungeons & Dragons' "Book of Erotic Fantasy" it is specifically averted. Your character's size has no impact at all on his sexual prowess. It also says a player can choose how big he is just like he can choose a character's eye color.
In the free hentai RPG Big Breasts Small Waist, the bigger a male character's...equipment is, the higher his Appearance stat is, and the more SEXP his partner gets from an encounter with him.
Discussed in Sid Meier’s Alpha Centauri. The quote for one of the technologies has Nwabudike Morgan saying "Gentlemen, forget what your courtesans have told you: size does matter!"
A handsome young Cyborg named Ace, / Wooed women at every base, / But once ladies glanced at / His special enhancement / They vanished with nary a trace.
Barracks Graffiti, Sparta Command
In Fate/stay night, Rin actually freaks out when she sees Shirou naked. She was a virgin and extremely nervous (so was Shirou, for that matter); Saber and Sakura are admiring, but not shocked. Shiki, on the other hand, managed to impress even the relatively experienced Kohaku.
In Boy Meets Boy, Mikhael's "freakishly large" penis is supposedly the main reason why his and Harley's sex life is so good, which in turn seems to be one major reason why their relationship is so good. It's really best not to over-analyzethis comic.
Averted in Cheer by Forview, a good-natured (and naturally NSFW) porn webcomic. If hand measurements are anything to go by, the boy is packing something like 8-10 inches. While the girls certainly enjoy themselves (and him), they do need to take care. The smaller girl is actually brought to tears by the discomfort until they find a way to negate the extra length, and even the bigger one needs him to be "super-gentle" with "the last inch".
Kyle from Juvenile Diversion is well endowed, which leads to some very enjoyable times for Jenny.
Peter of Peter Is the Wolf. Other than that one "feature", Peter is the runt of his pack; small for a human, let alone a werewolf. But he still keeps his girlfriend happy.
Of course, first time said girlfriend saw his wolf-form equipment, after she had changed back from her much larger wolf form, was "You put that in me?"
Jason from Something Positive may be both a use and subversion of this trope. One one hand, he was extremely popular with the ladies prior to his marriage, but, on the other hand, the only woman we've actually seen reacting to it onscreen responded with an expression of terror and the words "Uh, Jason? Could you please put that big...thing back in your pants? It hurts my pelvis to look at it." We don't see the appendage in question, so you have to use your imagination.
Richard of S.S.D.D was apparently named "Dick" for a very good reason. But then his girlfriend has an affair with a more modestly endowed guy because, to quote, "girls aren't hollow".
Rory from Teahouse, the youngest, shortest and most expensive of the courtesans because of his virginity, turns out to have an enormous penis, which persuades Lord Reed to become his exclusive client, despite the cost.
Occurs in the Whateley Universe to many male Examplars, to the point that an in-universe sex manual about Power Perversion Potential specifically warns about the danger of hurting one's partners through the sheer size of one's organ.
the character Phase's body was changed by his mutation to appear female, but his genitalia did not change, and in fact got BIGGER.
Occasionally pops up in Chakona Space, part of Garrek's popularity with vixens is suggested to be his "endowment". Leanna, being a genetically engineered (former) sex slave, is pretty large as well, no specifics but the only reason shi can look like a female is that hir penis is designed to retract into her pelvis. And speaking of genetically engineered sex slaves...
Sites like Literotica have a real problem with writers submitting stories where men have bizarrely proportioned genitals. Like a penis ten inches long and eight inches wide.
A great deal of transformation fetish stories involve people being able to "take" endowments that would be normally anatomically impossible, due to the virus/nanomachines/magic.
One story, by Nequ, deconstructed this trope, where a guy takes a pill that was supposed to give him a horse's stamina, but instead gives him a horse's endowment. Not only does this nearly kill him due to not being physiologically prepared for the transformation, leading to him blacking out, but it kills the woman he was having sex with. He's clearly traumatized by the incident.
A running gag in Archer is that Cyril's is bigger than the titular super-spy's and leads to his "sex addiction." At one point, Cheryl and Pam hack into ISIS's health care records and find that Cyril was covered for a penis "ensmallment." After that, Pam hints there are 'a whole twelve reasons' why Lana is dating Cyril.
Lana: Not to mention your... other... qualities...
Archer: Oh, so he just gets a pass? Like Milton Berle?
In the South Park episode "T.M.I.", the Colorado Surgeon General and Randy Marsh both propose equations for "adjusted penis length", with bigger being better. The trope is twisted a bit, since in both normal measurements and the "adjusted" ones, supposedly wimpy characters like Butters get top results.
Woody Johnson and the convict Meathammer from Brickleberry. Meathammer is only stated but presumably true since the entire prison population agrees with him, while Woody is seen naked on several occasions, with his censor bar reaching his knees. Denzel as well, playing into a common humorous stereotype about African Americans.
When Brian's ex-girlfriend returns with her new fiancee Derek in an episode of Family Guy, he quickly proves himself to be Brians superior in every single way, smarter, more handsome, kinder and richer. At one point, Brian resorts to following him into the bathroom to see if he has any "shortcomings". Judging by his response, he does not.