Greetings, all. It's been a while since I've last been here, so forgive me if this has been suggested by someone else.
As the topic states, I have a solution to the problem exhibited by the attached screenshot: an invisible undergarment fashion for the pants slot. Perhaps something consisting of only a pixel, or perhaps something of a color the client would render as invisible. Maybe an item that is small enough to manifest inside the player model when equipped.