One character has recently lost their virginity (or a pair of characters have recently lost their virginity together). This fact is immediately obvious to yet another character (usually, but certainly not always, an older woman), despite there being absolutely no outward sign or obvious reason to think that. The characters aren't acting cute together, there's no tell-tale Messy Hair or mussed clothing, nor even the subtle aroma of "just had sex".
The other character merely looks upon the new non-virgin, as if using Virgin Vision as a superpower, and they know (Women's Mysteries, perhaps).
- Futari Ecchi has Rika have the ability to tell whether someone is a virgin or isn't, just by looking at them. She mentions that she knew that Shouko, who is 24 years old, despite looking half her age, was not a virgin and flat-out points at Kyoko that she had finally lost her virginity, much to Kyoko's surprise and embarrassment.
- As an inversion, in the French comic Le Chant d'Excalibur, everybody can apparently detect that the heroine is still a pucelle, and will mention it at the first occasion.
- In Shakespeare in Love, Queen Elizabeth can tell that Viola has been "plucked since [she] saw her last." The Queen adds that "it takes a woman to know it," though she doesn't reveal how, exactly.
- This happens to the main character in Real Women Have Curves. Her mom figures it while watching Ana stand in front of a full-length mirror.
- In the West Side Story movie, Anita doesn't say it out loud, but she gives Maria this look that says it all.
- Ace Ventura: When Nature Calls:
"I believe they're saying she's not a virgin.""They can tell that?"(Cue being Chased by Angry Natives)
- In Say Anything..., Lloyd Dobbler's friends can tell that he and Diane Court "did the deed", despite Lloyd's "I admit nothing" disclaimers.
- Inverted in The 40-Year-Old Virgin, where the 16 year old daughter of the main character's romantic interest can tell he's lying about having had sex and is still a virgin. When he asks how she can tell, all she says is that she goes to school with tons of boys and can somehow "just tell" who's had sex and who hasn't.
- Subverted in Little Darlings, about two girls at a summer camp competing to see who can lose their virginity first. One girl (Tatum O Neal) had such a charming, romantic date with her target that although they didn't have sex, she returned to her friends with a silly grin and, as they put it, "your face is all shiny". So they're sure that she did it, and she doesn't correct them. Meanwhile, the other (Kristy Mc Nichol) does lose her virginity, but decides to deny it and is believed.
- In the Morganville Vampires, Claire fears this trope. Sure enough, Eve barely looks up and realizes what happened.
- In The Sound of Waves by Yukio Mishima, older women claim to be able to determine whether a girl is a virgin just by looking at her breasts.
- In The Dresden Files series, White Court vampires can sense virginity, which led to a surprise when Lara Raith (leader of the White Court vamps) met Carlos Ramirez (a Casanova Wannabe). Justified because they feed most particularly on sexual energy.
- The first chapter of Alina Adams figure skating mystery Death Drop starts with the researcher heroine listening to commentator insisting "You can always tell a virgin by the way she skates." She thinks the non-virgins skate better. She turns out to be right in her assessment of the skater they were watching.
- In Blue Smoke by Nora Roberts, Reena's mother is able to detect instantly that her daughter has lost her virginity when Reena arrives home after doing the deed. The scene is retained in the made-for-TV movie based on the book.
- In Fifty Shades of Grey, Kate could just tell that Ana slept with Christian.
- Not a virgin example in The Lost Fleet: Dauntless, but the first time Captain John Geary has sex after his 100-year stint as a Human Popsicle, the titular ship's captain, a young woman, immediately knows it, even though he's doing his best to act normally. When asking his sexual partner, she replies that this is a "need-to-know" kind of information. He interprets it as Women's Mysteries. To be fair, though, he does admit to himself that this is the first time he felt himself without "ice" inside him, so it's likely he was giving off subtle signals.
- In The Sound and the Fury, Ben, and only Ben, can detect the scent of his sister, which noticeably and irreversibly vanishes after she loses her virginity. Zig-zagged, however, in that Ben doesn't understand why her scent has disappeared.
- After Donna and Eric finally have sex in the third season of That '70s Show, neither one admits anything to the other characters (despite Eric really wanting to do so). When Donna goes to talk to Jackie, Jackie see her as having the words "I Had Sex" written on her forehead, and Jackie immediately rushes her away so they can talk about it. When Eric goes to talk to Bob, Bob sees Eric as having the word "Guilty" on his forehead, inidcating that Bob is suspicious, but Bob makes no sign of knowing what happened until he officially finds out a few episodes later.
- In the Buffy the Vampire Slayer episode "Innocence," Buffy's mom can tell there's something different about her daughter, but not what. Buffy was acting as if she had something to hide, but that's hardly unusual for her.
- There's a very similar scene in Veronica Mars. When Veronica comes back from sleeping with Duncan, Keith looks closely at her and says that she seems different.
- On The Fresh Prince of Bel-Air when Carlton loses his virginity, he discusses it with Will using code words because Ashley is in the room. When they leave and Hilary asks what's up, Ashley replies "Carlton lost his virginity."
- In Xena: Warrior Princess:
Guard, pulling Gabrielle aside: "Virgins only."
Gabrielle: "What, is it written on my forehead?!"