Fixed restraints that keep the subject's body upright or vertical (or very nearly so). This includes suspension, sitting, and kneeling restraints, as long as the main part of the subject's body (and focus of the image) is upright, rather than lying down, leaning, bent over, etc. For that reason, this would almost never be applied to glory_walls and similar where the subject is in a forced leaning position.
If the subject is also standing while restrained, add the standing_restraints tag as well.
If the character is upright, but the restraints aren't keeping them that way, that doesn't count as upright restraints. An example would be a character standing while their arms and legs are tied. Since they could lie down (or bend over), they aren't actually permanently restrained in the upright position.
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