Sometimes, the most explicit acts get the least explicit scenes. It can seem very strange when a French kiss, a make-out session, or other act of non-coitus is depicted far more sexily than actual sex.
The effect is natural enough. There are any number of reasons not to depict a sex scene, and far fewer to shy away from a merely erotic one. Sex may not fit the rating; it may not fit the tone; it may be intended as an act of loving union, and the slimy bits would distract; the author may know better than to tackle description of this kind; there might not be a way around the fact that sex is ridiculous for everyone but the people involved. Meanwhile, tamer acts offend fewer delicate sensibilities, are less likely to overwhelm the plot, and can wind down naturally at levels where cutting away from a sex act would be both awkwardly explicit and frustratingly vague.
The clueful writer plans for the contrast and makes it meaningful. The difference between lust and love is an easy overtone, as is the conspicuous absence of whatever caused a previous failure.
- A weird example coming from a series like Berserk. All sorts of graphic sex scenes - consensual or not - and various performances are depicted in the series, the Official Couple not excluded. While Guts and Casca are clearly seen having vaginal intercourse (in four different positions, no less) there is little to no detail of Guts performing cunnilingus on Casca aside from Guts spreading her legs apart and telling her to get ready and Casca looking down and then shuddering and moaning in pleasure. So it's really more of a chaste lust, lewd(ish) sex scene.
- In Three Colors: White, a failed attempt at sex is shown in all its glory to establish the desperation of the participants and of their relationship. Success much later on fades to white.
- The Hole has this in spades. Thora Birch and her romantic interest have a standing make-out-and-grope session, while the camera keeps them dead centre. Later, when the love interest takes her virginity, it's offscreen, and all we hear are her not-too-sexy grunting noises.
- In Picasso Trigger, both Hope Marie Carlton and Bruce Penhall are both naked in a jacuzzi and when they kiss, the camera cuts away.
- In Seven Things That Didn't Happen On Valentine's Day At Hogwarts, Or Maybe They Did, frenzied 15-year-olds grabbing at everything they can reach are described in detail, but 17-year-olds acting out of love are cause to cut to the following morning. (Also, everyone's gay. But that's another matter.)
- In A Brother's Price, all the sex scenes are like this. While it is only touching with clothes inbetween, we get full details, but once the clothes come off, it's only hinted at what they actually do. The scenes where we actually are told what goes where, with no cut, are the ones that aren't meant to be erotic.
- A hot'n'heavy scene in Cory Doctorow's Little Brother has a lot of sucking and moaning and lowering and brushing, and that's about when the tear gas comes down. When the couple has actual sex, the description cuts away.
- Twilight and its sequels go into detail about Edward and Bella making out, but the various sex scenes in Breaking Dawn were faded to black.
- The Finnish novel Häräntappoase.
- Shows up from time to time in the Nightrunner series. The kisses are described in great detail, from the physical to the emotional ramifications. But by the time the two leads actually become a real couple, the descriptions largely gloss over any specifics.
- Ashfall by Mike Mullin uses this as part of the book's limited comic relief.
- The Hunger Games. Katniss and Peeta share a make-out session that describes the kissing and the way it makes her feel in great detail. When they eventually have sex it's given so little detail that there's room to argue they didn't even have sex at all.
- In Sunshine, two characters at one point have very pleasant sex outside in the sunshine...and that's all we're told about that. When two characters stop at foreplay, the reader is given all the details up to and including how unhappy the viewpoint character is at stopping halfway through.
- Leisure Suit Larry 1: In the Land of the Lounge Lizards. After a game's worth of dirty jokes and innuendo in the quest to get Larry laid, impending success causes the game to switch to a black screen for fireworks and a developer's congratulation.
- This was standard procedure for love scenes in the Global Guardians PBEM Universe. Pretty much everything leading up to "the act" was on screen and fully described. But once it became a matter of penetrative sex, the focus of the story shifted to the curtains fluttering in the breeze, and things faded to black and restarted the next morning, and so on.