The midriff being exposed is [[Administrivia/PeopleSitOnChairs not a trope on its own]]. One of the following tropes may fit instead:

* AgeInappropriateDress: A character wears a revealing outfit even though they are too young or too old to do so.
* AuthorAppeal: The author puts several characters in midriff-revealing outfits because they like them.
* BareMidriffsAreFeminine: Female and feminine characters wear midriff-baring outfits more often than male and masculine characters.
* BedlahBabe: Middle Eastern women are portrayed wearing midriff-baring clothes.
* ChainmailBikini: A character (usually female) wears skimpy armor, even if it's impractical.
* ClothingDamage: Ripping open a shirt, which may result in baring the midsection.
* CustomUniformOfSexy: A character wears a uniform customized for fanservice, which can include a bared midriff.
* ExposedAnimalBellyButton: An animal with a visible navel may wear a crop top.
* ExposedToTheElements: A character wears an outfit inappropriate for the weather, which can include a bared midriff in the winter.
* {{Fanservice}}: Bare midriffs, like other forms of partial nudity, are often used in a sexualized context.
* FurBikini: A two-piece outfit made out of fur, often used for fanservice.
* GoGoEnslavement: An enslaved character is forced to wear revealing, often midriff-baring clothes by their captor.
* LingerieScene: A female character is shown in her underwear, typically bra and panties, for fanservice purposes.
* MeaningfulAppearance: A character's exposed midriff tells you something about their personality or background.
* MsFanservice: A female character who is there for eye candy, who will wear a midriff-baring outfit for fanservice.
* NoDressCode: A character gets away with wearing a midriff-baring outfit to school.
* NoNavelNovelBirth: A human's lack of bellybutton is a cue that they had an abnormal birth.
* ParentalFashionVeto: Midriff-baring outfits worn by teenage girls are a common reason for parental objections.
* SailorFuku: The Japanese sailor school uniform is already high-cut in real life, but media sometimes exaggerates it to reveal the midriff.
* {{Sarashi}}: One variation of the sarashi, wraps around only the chest, while the midriff is left bare.
* SchoolSportUniform: The ever-iconic Japanese PE shirt with thigh-revealing bloomers, which might result in exposed midriffs.
* SeashellBra: A mermaid or other aquatic-themed character wears a top made from seashells (or starfish, or other aquatic items).
* SensibleHeroesSkimpyVillains: A villain or antagonist wears a midriff-exposing outfit for fanservice, contrasted by heroic characters in less revealing clothes.
* SexyWhateverOutfit: A ridiculous fanservice costume can often include a bared midriff.
* {{Shorttank}}: A stock anime character, a female {{deuteragonist}} who usually wears shorts and a tank top, shortened shirt optional.
* {{Stripperiffic}}: A fantasy character wears a highly revealing outfit, which can include a bared midriff.
* SultryBellyDancer: A dancer who wears revealing clothing for belly dancing, often including a belly-baring top.
* TankTopTomboy: A female character wears a (possibly midriff-baring) tank top to indicate she is boyish or masculine in some way (such as an ActionGirl, TheLadette or a {{Tomboy}}).
* TertiarySexualCharacteristics: One way to indicate that a non-human character is female is to put them in midriff-baring clothes.
* WalkingSwimsuitScene: A female character always walks around wearing a swimsuit, typically a two-piece bikini.
* WorkoutFanservice: Women are often shown working out in midriff-exposing tank tops or sports bras.

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