General: height assist
This usually comes along with size_difference, especially for sex, but may also occur for group poses or portraits, or when someone is using something (like furniture or machinery) clearly designed for larger characters.
- on_top_of - when a character is entirely on top of another character. This would not count as height_assist unless they're using the second character to reach a third character, or some other higher object. (Please add a thumbnail to this page if you come across an example of that!)