The Invisible Wall

I hauled myself up onto the wide wooden windowsill to secure a proper vantage point over this unfamiliar territory. Outside, the world stretched wide under the morning light. Just as I planted my paws, a brazen sparrow dropped down on the outer ledge, twitching its tail without a shred of caution. I dropped low, bunched my hind legs, and lunged forward to defend the border—only to hit a cold, completely invisible barrier. Glass. Solid as rock and infuriatingly clear. The bird fluttered off without even acknowledging my strike. I raked the smooth surface with one paw; if this place insists on see-through rock walls, it could at least give a warrior fair warning.