Sorry, I'm Gay

"You're barking up the wrong tree, ladies."

A female character tries to seduce a male one, who doesn't want to be seduced. He rebuffs her advances by simply saying "Sorry, I'm gay", regardless of his true sexuality. This trope is meant to be gender-neutral but for some reason, "Sorry, I'm lesbian" usually just doesn't work as well (not that "Sorry, I'm gay" works all of the time for men either).

A subtrope of Ignore the Fanservice. The opposite of Mistaken for Gay. Not to be confused with Faux Yay, which is a behavior, while this is just a quick way to halt the seduction in progress; one can lead to the other, however.

A sub-trope of You're Not My Type. See also Incompatible Orientation, when the person is actually telling the truth. Compare to All the Good Men Are Gay, Last Het Romance and Dude, She's a Lesbian.

Examples of Sorry, I'm Gay include:

Anime and Manga

In Pretty Face, Dr. Manabi gets rid of his creepy Stalker with a Crush by showing to her that he's into guys (when in fact, he isn't).
Early in Princess Princess, Toru's cousin, who's a Stalker with a Crush, shows up to harass him. After several unsuccessful attempts to get rid of her, Shihoudani puts his arm around Toru's shoulders, gives the stalker a very catty look, and says "Sorry, he's taken." ...He then proceeds to kiss Toru on the lips to drive the point home. Toru and Shihoudani's relationship beyond that is up in the air, but there are plenty of further hints.
Two occurrences in Shinshi Doumei Cross: Takanari tells Haine and his many female admirers at school that he's gay (and that Maguri is his lover) to dissuade them from pursuing him; this isn't true. In one side-story, Maora, after taking up cross-dressing so that he and Maguri can marry, cheerfully tells him that now they can be together - to which Maguri says he's only interested in boys. Who look like boys.
Nezumi of No 6 once does this in order to get a prostitute away from Shion,

Comic Books

Transmetropolitan, Issue 9. Spider Jerusalem is the guy (obviously). His query: "Would you like to go out to dinner?"

Kisako St. Exupery, Director of Cultural Reservation Systems: Sorry, got plans tonight. And, well, I play on the other team, if you see what I mean.
Nurse: Sorry, I don't eat.
Random Girl: Sorry, no. I'm Breatharian. [Layman's terms: They don't eat, they just breathe.] ("How about going to bed with me instead" "I went neuter last year. Sorry.")
(And the coup-de-grace) Hannah Enkidu, SPKF Feedsite Listener: Sorry, no. I'm married, not hungry, infected with seven unknown diseases, gay, pregnant with lizards and clinically dead. [Just to twist the knife, she was on a live broadcast at the time.]

The Midnighter serial has Midnighter break it to a female time cop from the future the reason why he won't have sex with her. After some confusion as to what the words "gay" and "straight" actually mean, she explains that no one regards sexuality in that manner anymore and everybody just does everybody.
In a run on X-Men by Grant Morrison, Beast is approached by a woman who dumped him rather harshly a few issues previous. She seeks to get back together with him, and he rattles off a short list of reasons why he didn't want to, ending with "Also, I think I might be gay." This actually became a (sub)plot point for a few issues, with Beast eventually out-and-out saying to Cyclops that he only said it to make his ex feel bad.
In Action Comics Weekly there was a short-lived version of the Secret Six concept; one of the characters told a grateful rescuee this when she came on to him, which was The Reveal to the readers as well (he also Lampshaded the "rescue romance" concept).
In the Dark Reign arc of Young Avengers, when Enchantress hits on him, Wiccan, bewildered, responds with "I'm with someone. And gay! Did I not indicate that?! Very, very gay." It doesn't seem to deter her, though.
In Stormwatch 46, a rare Breather Episode, Fahrenheit, Jenny Sparks, and Flint are at a restaurant in Paris, and Fahrenheit has already picked up a hot guy, but when she calls Flint over to translate what he's saying, it turns out what he was trying to tell her was he's gay. Fahrenheit jokingly suggests that the three women kidnap him and "keep at him until he starts liking girls..."
A male-to-female version in Punisher:

Soap: You know, Molly... you're really...
Molly: A lesbian.

The campy spy send-up Codename: Knockout explores the adventures of super-spy Angela Devlin and her gay sidekick "Go-go" Fiasco. At one point a super-villain's seductive "assistant" attempts to seduce Go-go for information:

Anita: Don't be coy with me Mr. Fiasco. You're a man, I'm a woman...
Go-go: I'm not coy, I'm gay.
Anita: ...GAY?
Go-go: Yeah, GAY. Pansy, Fruit, Invert, Fairy, Back-Door Boy -- The lot. I'm here, I'm queer, let go of me! You get the picture.

Veronica from Archie Comics is smitten by the new guy, Kevin Keller. He has to let her down gently since he's, well, gay.

Fan Works

There's a Knights of the Old Republic fic taking place at the Sith Academy on Korriban. Carth, passing as a the PC's slave, manages to attract the attention of Lashowe, one of the students. His last-ditch effort to dissuade her before actually breaking cover to run or fight was "Sorry, I'm a eunuch!"
- Sounds like So Not My Problem, where the PC or Revan is a Chaotic Neutral Loony who only really cares for credits or droids. Because of this he gets to poke fun at all the glaring flaws of both the Jedi and the Sith.
- Probably a Shout-Out to Baldur's Gate 2, where a Male PC gets hit on rather forcefully by a Drow priestess and can resort to the same excuse.
Nukicide's hilarious F.E.A.R. Troll Fic Beyond the Final Door has a character named "Fast Soldier" use this as his main defense against Alma's Attempted Rape.

Then stupid gurl try and has sexy time with Fast Soldier but Fast Soldier is fag so he pushd her off.

Film

In The Specials, Amok makes a pass at Power Chick who thinks he's joking because she's openly gay, even bringing up that she was on the cover of The Advocate.
Tank Girl. To stop Sgt. Small's sexual harassment of Jet Girl, Tank Girl kisses her in front of him and says Jet Girl is her girlfriend. Small reacts with disgust and leaves.

Jet Girl: It worked!
Tank Girl: [innocent smirk] What worked?

Half Baked:

Brian: Hey, Jan... will you be my girlfriend?
Jan: Well, I would, but I'm gay. I'm a big dyke.
Brian: Oh. What's that like?

In What Women Want, Mel Gibson's character has used his powers of Telepathy to seduce a hot, but insecure, barista. The barista chases him up afterwards, and demands to know why he's been avoiding her ever since, putting it to him that he "must" be gay because he talks and thinks like a woman. When he overhears her frantic thoughts that she can't bear to be rejected for any other reason, he decides to go with it.

Literature

Done in the YA lit book Another Kind Of Cowboy. He's telling the truth, though.
In the novel Fluke, Nate resorts to this, because he's finding it incredibly difficult to have a conversation with a naked woman who won't stop trying to seduce him.
Spellsinger features a gang of rogues trying to lure a unicorn with a virgin. It doesn't work on this particular unicorn, because they use a virgin GIRL.
Stephanie Plum uses this one to discourage an admirer while getting him to keep talking to her and giving her information she needs about a case. Lula helps out by playing Stephanie's girlfriend.

Live-Action TV

Mystery Science Theater 3000: This was one of Mike and the bots' riffs from Danger: Diabolik. Diabolik's girlfriend shows some leg in order to hijack a truck. One of the SOL crew says, "Sorry, I can't help you. I'm gay."
How I Met Your Mother: While on a girls night out, all of the men in the bar are hitting on Robin while completely ignoring Lily.. She soon figures out that it's because of her engagement ring and takes it off (at Marshall's suggestion, no less!) to see how many men she can attract. When one guy finally approaches her, she suddenly becomes horrified at her "infidelity", putting the ring back on and rushing into an explanation of why she took it off—only for the guy to cut her off with, "Yeah, I'm gay. I just came by to let you know you sat on a grape."
Frasier's dad plays along when he is Mistaken for Gay by a woman at the Opera, because he wants to evade her advances. So she tries to hook Martin up with her brother.
NYPD Blue: Licalsi pretended to be gay to discourage Martinez. He backed off at least somewhat (so it did work), but later she outed herself as straight-but-not-interested.
Hustle:
- In one episode, the target of a Bavarian Fire Drill comes on to Stacey. She replies "Sorry, I'm gay," which doesn't entirely dissuade the man she's talking to, who tries to find out if she and her fictitious partner would both be willing to- you know.
- Played with in another episode, where Danny gets rejected by a pretty hotel receptionist and decides that she must be a lesbian. At the end of the episode, it turns out that he's right.
Used in Torchwood with the evil alien in a human body who derives energy from sex picking random blokes from the waiting area of a sperm bank and literally dragging them off to bang them. One of the men tells her (in an effeminate Welsh accent): "Oh, I don't think so, love, I'm gay!" Not that it helped him very much.
In Everybody Loves Raymond, Robert tries to find a way to break up with his immensely hot girlfriend. Due to her aforementioned hotness, no one can believe that he actually wants to break up with her (even though she is the most irritating woman on the planet). Robert finally goes to her ill-tempered Italian father to explain "I have to tell you something: I am a homosexual."
In one episode of The Bill, fat, balding, crime scene tech Eddie tried to chat up big-breasted DC Jo Masters. She took him to a bar after work to explain (off-screen) that she was a lesbian.
In The First Shop of Coffee Prince, Han Kyul hires Eun Chan to pretend to be his gay lover and show up during the dates his mother has set him up on, to scare away prospective girlfriends.
On season 4 of Weeds, Nancy's former best friend Celia is spying on her for the cops. Nancy quickly claims that Celia is her girlfriend, who suspects Nancy of cheating on her. This convinces Guillermo both that Celia is not a spy and that Nancy is not on the market and he should stop pressing his luck. Later, when Nancy's love interest brings up the issue of her "girlfriend" Celia, Nancy smiles and says that it's easier to be friends with Guillermo when he thinks she's a lesbian.
Inverted on My So-Called Life, as when Rickie finds out that Delia has a crush on him, he tries feebly to ask her out...only for Delia to tell him that she knows he's gay, and that she only has a crush on him because she wants one that "can't hurt so much".
Played for Laughs in Degrassi the Next Generation. When Marco is helping Ellie move into her dorm, she introduces him to her roommate. "Oooh, he's cute, you'll have to tie the sock on the doorknob when he comes around," she coos, and he smiles, sticks out his hand to shake and says, "Hi, I'm gay."
In Misfits, ineffectual Time Master Curtis accidentally gets caught in a Groundhog Day Loop and finds himself having to break up with Samantha numerous times. He makes various foolish excuses as he tries to find the least upsetting way of dumping her, and claiming to be gay is one of the first things he tries. It backfires massively, as Sam sees it as a huge betrayal that made their whole relationship a lie.
Jake 2.0 used the girl-is-a-lesbian variant, but interestingly, it was treated exactly the same way as the guy-is-gay variant. Then again, Jake's not the type to suggest a threesome.
Hilariously done in Lost in Austen when Amanda tries to convince Mr. Bingley that nothing could ever happen between them.

Mr. Bingley: "I am drawn to you! I am a man!"
Amanda: "And I'm a woman! And I'm drawn to... other women."
Mr. Bingley: "So... you mean there really are women who... steer the punt from the Cambridge end?"

In Lost Girl 1x06, the protagonist is trying to charm her way past a security guard without using her succubus powers on him.

Bo: I just love a man in uniform.
Guard:Honey, that makes two of us.

On the Glee episode "Sexy," two of the girls from Dalton's sister school were apparently charmed by Blaine's performance with the Warblers of Animal by Neon Trees and try to give him their phone numbers, asking him to call them. His response? "Sweet, but not your team."
Inverted in the Modern Family episode "Treehouse". At a bar, Cameron (played by Eric Stonestreet, whose real-life heterosexuality made this more amusing) successfully bets his partner Mitchell and another gay friend that he can get an attractive woman at the bar to give him her phone number.
Warehouse 13 had Jinks and Claudia together on their first mission. After a series of misunderstandings, including Claudia Lampshading their supposed UST he stops her with this line. Commence awkwardness.
The Jori shippers were put in mind of this trope in the episode of Victorious where Jade and Tori were forced to go on a "date" for an assignment, then immediately hit on by two obnoxious guys. Their song, "Take A Hint," is basically this trope in song form.

Newspaper Comics

In an early FoxTrot comic, Paige was trying to avoid being asked out by Morton Goldthwait and thought of several excuses she could use, including this one.

Professional Wrestling

On an episode of WWE Raw, Stephanie McMahon, who has been banned from the building, tries to seduce an usher to let her inside. His response? "Stephanie, I'm gay." To add the exclamation point, he commented on Billy and Chuck, who just walked by, stating that if they released a calendar, "they could make millions!"

Video Games

In The Longest Journey, when April tries to get past a security guard by acting cute, all he says is "Sorry, ma'am, but I'm gay".
Another female example in Vampire: The Masquerade Bloodlines, where one woman can turn down a male Player Character by telling him "I just remembered, I'm gay."
- Then Inverted if playing a female character, where she'll say "I just remembered, I'm straight."
In Princess Maker 4, Marie (one of the player character's daughter's possible best friends) gains a very persistent Stalker with a Crush. She finally manages to get rid of him by telling him she's not interested in men and is dating your daughter (who, playing along, tells him to back off of her girl).
Played with in Dragon Age: Origins; "barking up the wrong tree" is the exact phrase used to turn down offers for same-sex romance.
- Leliana says that she is a "poetess" to put off a crazy Templar. This is half true

Web Comics

Order of the Stick
- Elan tried to get out of prison by tempting his guards with an illusion of a woman—only to find that one guard was married and the other gay.
- In a bonus comic from one of the books, Miko tries to attend dinner with two other female paladins to celebrate new years. Her overbearing personality gets on their nerves, and they claim that they are dating so that she will let them have some alone time. In an interesting twist, the two then ponder whether they will have to atone for their lie to keep their paladin powers, and one suggests that they could actually make out instead. Later on they are seen in a restaurant doing just that.
Sam and Fuzzy lampshades this here. Extra bonus: pretending to be gay is actually the second lie - the first was pretending to be a guy!
Ethan from Shortpacked refuses Conquest's advances with this. He did sleep with her earlier (and enjoyed it too), but only realizes he's gay after he's told that he's supposed to be.
Keychain of Creation has Marena's attempt to seduce someone result in this. Takes a slightly unusual result, as she's a Gender Bender, and he's a currently genderless gay transformer.
In Gorgeous Princess Creamy Beamy, the gay alien-posing-as-exchange-student X Hoshibana befriends Schoolgirl Lesbian Cheesecake St Cherrywell, much to the annoyance of The Girls Of The Class:

"Hey! You're not supposed to LIKE Cheesecake! You're supposed to be disgusted because she's so lezulated!"
"You guys do know that I'M gay, don't you?"
"NNNNNNN! WE ... REFUSE ... TO ... UNDERSTAND ... THAT ... SENTENCE!"

Similar to the above FoxTrot example: in an early Penny and Aggie strip, Aggie considers several possible responses to turn down a boy who asks her out, among them "I'm not even sure I like guys." She later thinks, "Ironically, that one's sorta true, and it just makes them more interested."
The entire premise of Girl's Only is a group of guys in a school with too many aggressive females pretending to be gay so the girls leave them alone. They take it a bit farther though...
The Las Lindas bonus comic, "Building an Empire" has Tootsie turn down an offer of dinner at her moms, because a snobby guy she doesn't like will be there. When she asks why she doesn't like him, she responds with the infamous line, "I'm busy being a lesbian, okay!?". She claims to be kidding. Alej(And the fanbase at large) have their doubts.

Web Original

Played with in this The Legend of Zelda parody:

Ganondorf: Sorry ma'am, I'm gay.
Zelda: Oh... well, now I'm Shiek!
Ganondorf: Now I'm NOT gay.
Shiek: Nothing I do pleases you!

Speaking of Zelda, this has been used plenty of times in sex joke CD-i YouTube Poops, as an excuse for Link to fuck Ganon instead of Zelda or some such. For example, this one.
This Failbook example.

Western Animation

On The Simpsons, "I am gay" was Homer's suggestion to Bart as to how to let Bart's teacher down "easy" after Bart sent her a series of prank letters pretending to be a man responding to her personal ad. Homer's suggestion to Lisa re Ralph was "Six simple words: I'm not gay, but I'll learn."
In an episode of Futurama a stereotypical musclebound beach bully picks on Fry while flirting with Leela. Leela actually agrees to go with him, only for the bully to explain that he's a gay "professional beach bully," meaning he picks on weaker guys and then throws fights against them for money, allowing the guys to impress their dates.
On South Park, Chef tries to seduce a substitute teacher, Miss Ellen, only to find out that she is a lesbian. The boys, who all have Precocious Crushes on her, don't know what a lesbian is, and a flustered Chef explains that it means she only dates other lesbians. Naturally, the boys decide to become lesbians themselves, and Hilarity Ensues.

Real Life

Pop star Ricky Martin, who came out of the closet as a gay man in 2010, has remarked that despite having publicly stated both his homosexuality and that he is a relationship with another man, women still proposition him.

Ricky: “They say very beautiful, very erotic things to me about what they want to do with me, which is nice, but I’m not interested.”