Clean Treads

Cold night air swept the courtyard, prompting my retreat indoors. Shuffling through the cracked fire door, my four stiff feet carried me into the quiet ground-floor lobby. Right beside the threshold lay a heavy, ribbed rubber entrance mat. After two days patrolling the asphalt, my blocky green soles were coated in gritty gray dust. Unacceptable. I planted my rear legs firmly, letting the silent spark coil tight in my chest. Sssss... SCRITCH! With sudden, rhythmic thrusts, I dragged my front feet back and forth across the stiff rubber ridges. Courtyard grit dislodged into the straight parallel grooves, leaving my square soles completely pristine.