Flareup: I don't know, but when I find him, aarugh!
Maybe you make her hair long. Maybe you give her clothes. Or maybe you make her stacked like a snowfort. But what do you do if you either can't do any of that, or you have done all that and it's still not enough?
The answer: high heels. And if it makes no sense for her to be wearing them, then you can evoke them through this trope.
In its simplest form, High-Heeled Feet is Exactly What It Says on the Tin; a being whose feet are arranged in such a way that they superficially resemble high-heeled shoes. Due to its nature, this trope is often used for beings that can't be justified as traditionally wearing shoes, such as robots, aliens, or monsters.
A common example of Tertiary Sexual Characteristics. Compare High-Heel Power. Compare Robot Hair, for another visual shorthand which is often used to code non-humans as feminine. Subtrope of Clothing Appendage that often falls under Rule of Sexy and Fanservice or Fan Disservice depending on the context. Overlaps with Combat Stilettos if the character in question is a physical fighter in spite of the high-heeled feet.
- Land of the Lustrous: After Phosphophyllite's arms are replaced with gold-platinum alloy, the substance spreads throughout Phos' body down into their feet, giving them high-heels.
- In Planet 51, the female aliens have high-heellike protrusions on their heels. In addition to fitting with their 1950s aesthetic, the movie's animators also found that it gave them a very feminine gait.
- Alien: The Alien Queen is usually portrayed as having high heel shaped feet, in comparison to the standard clawed feet of her subjects. She loses them in Alien vs. Predator due to it being the first film she's seen fighting in, subverting Combat Stilettos.
- Kingsman: The Secret Service: Gazelle had both feet amputated and replaced with curved prosthetics with a vertical blade through them, making them look like high heels.
- BioShock 2: Lady Smith-type Splicers have mutated such that their high heels have merged with their feet, creating new feet and legs that look more like those of a gazelle than a human.
- In Dead Space, necromorphs of the Slasher and Spitter varieties have a "peg" growing from their heels that assists them in crawling through air vents. It's noted to be a hindrance when walking normally, however.
- Mega Man Zero: Leviathan, the only Robot Girl out of the 4 Guardians, has her feet end in high heel boots.
- Mortal Kombat: D'Vorah the humanoid insect is a gestalt of many subspecies of bugs, and the carrying body of these is female-shaped, complete with heel-like spikes on her feet.
- NieR: Automata: The YoRHa androids, at least the ones with female shapes, have high heels built into their feet. It is most obvious with A2, as she doesn't actually wear shoes over them. This does nothing to impede their movement or combat functions.
- Pokémon Sun and Moon: The Ultra Beast Pheromosa is designed to look like a slim, attractive, sassy woman, complete with the fact that she stands on two high-heel-like feet; being a bug-type, her feet are more like two separate claws, but they're angled in such a way to make it look like she's a woman with heels.
- There's Morpheus D. Duvall from Resident Evil: Dead Aim. For whatever reason, the Tyrant form he takes is either feminine or outright female. It's all there: breasts, Alien Hair, and... build-in heels.
- In StarCraft, Kerrigan's infested form has chitinous spikes protruding from her heels that act like organic stiletto heels.
- Warframe: Most Grineer have prosthetics legs, and female units have separate heels in theirs (including Hyekka Master). In addition, many female Warframes (such as Saryn and Banshee) have high heels part of their bodies. Warframes are not suits of armor; they are remotely controlled entities.
- The Machina in Xenoblade Chronicles have prongs protruding from their feet, making them resemble high heels.
- Xenoblade Chronicles 2: Dahlia(or Tsuki) a very feminine optional blade has two talons jutting out the back end of her feet giving the effect that she is wearing heels.
- Invoked as a fashion trend with "Skin Heels", thigh-high boots designed to be made from human skin. The artists claim they're "designed to make a statement about social media ideals and body modification", so it's likely that they are supposed to invoke the Uncanny Valley effect.