The ornamental design for pants with rear openings, as shown and described.
The sole FIGURE is a rear elevational view of a pants with rear openings showing my new design.
The uniformly spaced broken lines on the surface of the pants represent stitching. The dot-dash broken lines mark the boundary of the claimed design. The remaining broken lines, showing a waistband and portion of the human form, show details which form no part of the claim.