Sideless outfit is main for exposing the sides of the body in large areas, but recently some new related tags are main for only exposing the sides of the upper body. Even the wiki directly says that exposes the sides of a character's chest.
I think many of the styles that only expose the side of the upper body are closer to high-waist sideboob, which is quite different from the style that exposes a large area of the sides of the body.
I hope we can distinguish these two types and not use them all as sideless outfit.
Tags such as sideboobless outfit or partially sideless outfit can also be considered.