The Thumping Box
A low rumble vibrated straight through the floorboards. I tracked the sound toward a tall black cabinet. Climbing the stacked books next to it gave me enough height to haul myself onto its mesh top. The entire surface pulsed rhythmically under my claws. I slammed my foot down to test its pushback. The box buzzed deeper, sending steady tremors through my legs. A perfect vantage point, and it hums with real weight.