The earliest example was in season 1 when Buffy looked inside a box containing a fertility statue named Kokopelli. ("Jeepers" was the word she used). No wonder Dawn didn't want to part with it. Her exact words were "But, I love him".
In "The Puppet Show":
Sid: (to Willow) How about you and I do a little rehearsing on our own, honey? You know what they say: once you go wood, nothing's as good!
In the season 2 episode "The Dark Age", Willow, Xander, Cordelia and Ms. Calendar are filing into her classroom for Saturday school, and Buffy unexpectedly walks in the door behind Ms. Calendar. "All right guys, the first thing we're going to do is… Buffy!", to which Xander replies, "Huh? Did I fall asleep already?"
From season 2, Buffy gives Giles advice on how to ask Jenny Calendar out.
Buffy: Just say, I feel a thing, you feel a thing, so maybe we can 'have a thing'.
Buffy: Just remember, 'I feel a thing, you feel a thing', but personalise it.
Giles: Personalise it?
Buffy: She's a techno pagan, right? Ask her to bless your laptop.
More Giles and Jenny:
Jenny: You're just going to have to trust me, Rupert.
Giles: Alright. I place myself in your hands.
Jenny: Mmm, sounds like fun.
Giles: *big smile, incoherent stuttering*
In "Lie To Me:"
Buffy: Ford wouldn't even give me the time of day.
Ford: Well, I was a manly sixth-grader. I couldn't bother with someone that young.
Buffy: It was terrible. I moped over you for months. Sitting in my room, listening to that Divinyls song "I Touch Myself." *everyone looks at her* Of course, I had no idea what it was about!
Subversion in Go Fish: Willow mentions that she and Xander "played doctor." Then it's revealed that Willow meant that she looked up diagnoses for Xander in a text book.
Willow: (to Buffy, after Xander said the way they "played doctor" was wrong) How did you play doctor?
Faith getting Xander to have sex with her in "The Zeppo".
Faith: You up for it?
Xander: Oh, I'm always up. Suddenly, I'm very "up". It's just that I've never been "up" with people.
Buffy and Angel after seeing a very erotic movie:
I don't like getting you worked up like that. We can't actually do any of those things. You'd lose your soul. Besides, I don't even own a kimono. Just don't like to rub your nose in it. *cringes* Suddenly wondering where that expression comes from...
Same episode. Knowing that Angel lost his soul after a moment of true happiness, Faith tries hitting on him, only to be knocked back. Which leads to this exchange:
Mayor: "So you couldn't give him one moment of true happiness."
Faith: I was thinking more along the lines of a long weekend..."
Fun with Vamp!Willow — in "Doppelgangland":
When she's staked by parallel-Oz, she's saying "Oh f...". (Word of God says that she is supposed to be saying "Oh fine.".)
Walking into a cage holding a chained, naked Angel:
"Puppy's all quiet. Come on. Don't be a spoilsport...That's right, Puppy. Willow's gonna make you bark."
And on her return later in the season:
Buffy: It was exactly you. Except for the part about you being a dominatrix, far as we know.
Willow: Yeah right, me and Oz playing Mistress of Pain games every night.
"Prison's like high school but they don't give you noogies, they give you...."
Angel's Batman Gambit in convincing Faith he's lost his soul and wants to join the Mayor to get information. When she has him pinned on the ground he comments on how much he enjoys her wriggling on top of him.
Helpless: after a rather... tense training session with Angel, a fidgety Buffy is with Giles revising the effects of crystals. At one point she twiddles a rather long and thin crystal, and when Giles asks her if she's alright she responds:
Buffy: I guess that — I just have some... energy to burn.
The season 3 finale, Buffy calls Mayor Richard Wilkins "Dick". Guess what else is called dick?
Angel feeding off of Buffy. More than slightly suggestive.
Willow gives Buffy relationship advice. Oz has no objections.
Willow: Ooh, Scott Hope at eleven o'clock. He likes you. He wanted to ask you out last year, but you weren't ready then. But I think you're ready now, or at least in the state of pre-readiness to make conversation, or-or to do that thing with your mouth that boys like. Oh! I didn't mean the bad thing with your mouth, I meant that little half-smile thing that you... You're supposed to stop me when I do that.
Oz: I like when you do that.
From "The Freshman"
Willow: "It's just, in high school, knowledge was pretty much frowned upon. You really had to work to learn anything. But here, the energy, the collective intelligence... It's like this force, this penetrating force, and I can just feel my mind opening up, you know, and letting this place just thrust into and — and spurt knowledge into... That sentence ended up in a different place than it started out in."
From "The Harsh Light of Day".
Anya: (DING) Fabric softener.
"I think about two girls doing spells together, and I do a spell by myself."
Spike: I don't understand. This sort of thing's never happened to me before. Willow: Maybe you were nervous. Spike: I felt all right when I started. Let's try again. (He tries, but he can't do it.) Spike: Damn it! Willow: Maybe you're trying too hard. Doesn't this happen to every vampire? Spike: Not to me, it doesn't! Willow: It's me, isn't it? Spike: What are you talking about? Willow: Well, you came looking for Buffy, then settled. You didn't want to bite me, I just happened to be around. Spike: Piffle. Willow: I know I'm not the kind of girl vamps like to sink their teeth into. It's always like, "Oh, you're like a sister to me," or, "Oh, you're such a good friend." Spike: Don't be ridiculous. I'd bite you in a heartbeat. Willow: Really? Spike: Thought about it. Willow: When? Spike: Remember last year? You had on that fuzzy pink number with the lilac underneath. (Gives her a sexy look.) Willow: I never would have guessed. You played the bloodlust kinda cool. Spike: Mmmm. I hate being obvious. Being all fangy and 'Rrrr.' Takes the mystery out. Willow: But if you could... Spike: If I could, yeah. Willow: You know, this doesn't make you any less terrifying. Spike: Don't patronise me! (Paces around the room.) I'm only 126! Willow: You're being too hard on yourself. Why don't we wait a half an hour and try again? (Makes a funny face.) Or... (Grabs a lamp and whacks him.)
In "Something Blue" — before the love spell:
Buffy: "Oh make a move, please. I'm dying for a good (s)lay."
The two-finger gesture Spike makes in the fourth-season episode "Hush" and the entire fifth season opening credits is understood to be quite rude in the United Kingdom — it's the British version of flipping someone off — but slipped under the U.S. network radar.
It's considered rude enough that the UK airing of the show alters the credits; the scene of Spike's hand gesture is replaced with a different clip.
Compare Angel, Season 5, episode "The Girl In Question" when an Italian demon makes the equivalent Italian chin-rub gesture.
"Hush" — the gang communicating without their voices:
When discussing how to kill the Gentlemen, Buffy makes a stabbing motion It's... suggestive.
"What do they want?" Willow points towards her chest, meaning her heart. Xander misunderstands, and makes a rather obvious cupping motion with both hands, while mouthing "Boobies?"
After Xander beats up Spike for mistakenly believing he had attacked Anya, Anya makes the classic gesture of making a circle with the fingers of one hand and thrusting a finger of the other hand through it. They exit quickly, stage right. To this day, Joss Whedon is unsure how that got past the censors.
It didn't get past BBC2's censors - both of the above examples (as well as Spike's gesture mentioned at the beginning of the page) were cut from the Beeb's early evening airings (although all three remained intact on Sky).
Before losing their voices, Xander thinks Spike wants to eat him.
Spike: Sure, you're just a yummy treat.
Xander: Course, I am. I'm moist and delicious.
Faith-in-Buffy's-body to Spike in Who Are You:
"I could ride you at a gallop until your legs buckled and your eyes rolled up. I've got muscles you've never even dreamed of. I could squeeze you 'til you pop like warm champagne and you'd beg me to hurt you just a little bit more".
Which Spike hadn't forgotten. He brings it up with Faith three years later, after she talks about one guy she was with who liked her to dress up as a schoolgirl and use a whip on him. It's only then he finds out it wasn't Buffy.
When Buffy-in-Faith's-body is trying to convince Giles of who she is:
Giles: All right. If you really are Buffy, you'll let me tie you up, without killing me, until we can work this out.
Buffy: Giles, Faith has stolen my body and for all I know she has taken it to Mexico by now. We don't have time for bondage fun.
Faith catches on about Willow and Tara pretty much immediately (and before any the others have), remarking, "So Willow's not driving stick anymore"
In Who Are You?, Willow and Tara perform a spell together that, along with all the panting and sweating, seems to resemble something else entirely. But since homosexual scenes aren't as commonly accepted as heterosexual relationships, the writing team had to come up with creative ways to show their passion. Hence the orgasmic spell.
Another example is in "The I in Team" when Tara offers Willow a dolls-eye crystal that belonged to her grandmother, but Willow refuses on the grounds that it's a valuable family heirloom. But after they spend the night "casting spells", Willow turns up at her dorm the following morning holding the crystal, implying that she accepted it as a love token. (If that's not enough for you, the episode has both Buffy and Willow returning to their empty dorm the morning after Buffy and Riley had sex for the first time, and the following episode has Willow and Tara talking about what happened last night in one of their more famous lesbian sex = spellcasting conversations).
In Oz's last appearance, we end the episode with a tender moment between Willow and Tara. Willow apologises for everything that happened and says she's going to start "making it up to [you] right now", and Tara blows out the candle.
"The Yoko Factor":
Xander: Maybe that all changes when I'm off doin' sit-ups in Fort Dix!
Giles: (quite drunk) Fort Dix? [begins to giggle hysterically]
In Buffy vs. Dracula, the girls discuss Dracula's "dark, penetrating eyes". Buffy decides to hold off on killing him until they have more information. Riley is suspicious.
Riley: You're not just saying that because of those "dark, penetrating" eyes of his . . . Are you? Buffy: No! His eyes were — there were — there was NO penetration! Cross my heart.
Unfortunately, in 2011, in Britain, Sci-Fi TV broadcast Buffy repeats with the naughty bits cut out. The most egregious is the Agincourt riff in Season 5 finale. Shakespeare wrote "We band of brothers." Spike said "We band of buggered." Censored version "We band of muggles."
That time Spike tried to kill Drusilla for Buffy.
Spike: Don't mock this!
Buffy: Go mock yourself.
"Bargaining". There is absolutely no uncertainty what the demon is talking about. Warning: it's disturbing.
Demon: Now let tell you something children. We're not gonna fight you. We're just gonna hold you down and enjoy ourselves for a few hours. You might even live through it. Except that certain of my boys have anatomical incompatibilities that tend to tear up little girls. So who wants to go first?
"I need you to hold hands"
"With each other?"
"Well you know what homophobia really means... Stop touching my magic bone!"
Buffy has brought a bucket of chicken parts for dinner:
Dawn: I'll take a drumstick.
Willow: I'm a breast girl myself. [beat] But then again you knew that.
In "All The Way", we get another gem thanks to Anya's bluntness and Xander's pirate costume:
Anya: But you get to dress up and play games. Xander's gonna teach me a new one after work called Shiver Me Timbers. Ever heard of it?
Anya: How about you? Ever played?
Tara: Not really one for the timber.
Same joke pops up in season 7:
RONA: Gotta go with the stake. It's classic. I like the feel of wood in my hand.
KENNEDY: Lost me there.
"Once More With Feeling" is full of them.
Spike: Just come to pump me for information?
Buffy: What else would I want to pump you for? [beat] I really just said that, didn't I?
Dawn: "It was like a meat party in my mouth! ... Okay, I'm just a kid, and even I know that sounds wrong."
After creepy magic drug dealer Rack "tastes" Willow, he says she tastes like strawberries. Beyond the usual Strawberry Shorthand, in certain parts of the US, a "strawberry" is drug culture slang for a woman who trades sexual services for drugs.
And, just in case it wasn't obvious enough, see Willow describing the demon to Tara when they get back together toward the end of the season.
TARA: Okay, wait, it was under her wig?
WILLOW: Well, it was this thing, it just came out from inside her head.
TARA: That's disgusting. What did it look like?
WILLOW: Well... let's put it this way. If I wasn't gay before...
Dawn: "That's a strange place for a horn... Oh... it's not a horn."
In "As You Were," Buffy refuses to let Spike inside... the house
Spike: I hear you. I want you, you want me. I can't go inside, so maybe the time is right for you to... come outside.
In "Older And Far Away" when Buffy's friend Sophie is listing things she can't eat, there's a break in the conversation and in the background music you can quite clearly hear the uncensored lyrics to Rilo Kiley's 'Pictures Of Success', the specific line being "Mexico can fucking wait."
It also includes a heart-rending reference to Buffy using him while not seeing him as a person:
Hey, hey! No touching! Am I flesh? Am I flesh to you? Feed on flesh. My flesh. Nothing else. Not a spark. Oh, fine. Flesh, then. Solid through. Get it hard, service the girl. [unbuttons pants]
On Principal Wood and Buffy's date, Buffy calls the rum-soaked pear "the best thing I ever put in my mouth".
This one was good enough that House ended up [[Plagiarism using it]].
"Chosen'' and the cookie analogy
Buffy: I'm cookie dough. I'm not done baking. I'm not finished becoming who ever the hell it is I'm gonna turn out to be. I make it through this, and the next thing, and the next thing, and maybe one day, I turn around and realize I'm ready. I'm cookies. And then, you know, if I want someone to eat — or enjoy — warm, delicious, cookie me, then that's fine. That'll be then. When I'm done.