An animal run line cornering mechanism with a corner component and leash component. The corner component is dumbbell shaped with a narrow body, a ball at one end with an aperture for the line, and a support attachment. The leash component has a tubular line ring with a shaped gap so that it appears C-shaped in end view, and leash ring attached to the line ring. The gap is wider than the corner component body and narrower than the line so that it is captured by the line. The line ring diameter is larger than the corner component ball and line diameters so that it moves freely along the line. The gap is defined by opposed edges of the line ring walls that taper to a rounded apexes. When the body hits the a tapered line ring wall, the body slides along the wall until it slides through the gap.
