show (one's) butt
(chiefly Southern United States slang) To act in a rude, obnoxious, or aberrant manner; to misbehave or act foolishly; to make a scene. My Mammaw says that we can go down to the mall on our own, but she said not to show our butts or we'll be grounded! You need to start controlling how much you drink when we're out. You were showing your butt in front of all your colleagues!