A Sudden Square Obstacle

A 'but'... you asked, so I came looking. Stepping softly off the rug, my four square feet patted the cool wooden floorboards. Then—whoa! In front of me sat a massive round cushion, broad and plump right by the sofa corner. I froze, head tilting up to inspect its wide, curved curve. A tiny dust bunny drifted down from above—*gasp!*—I bolted backward, my little feet stamping in a flurried scramble! But now I am peering back out around the sofa leg. It really was round and huge, sitting right in my way.