A Foreign Obstacle (don't mind the two heads)

I dropped from the porch railing down to the stepping stones below to advance along the outer perimeter. Near the border where flagstones meet gravel, a discarded brass key sat half-buried under a damp oak leaf. I brushed the decayed leaf aside with one glove and gripped the metal stem. It was cold, tarnished, and possessed a grooved edge cut with geometric precision. Using both hands, I leveraged it upright against the lip of a raised stone border to inspect the mechanism of its notches. It does not belong to the porch door, yet its craft is deliberate. I set it securely between two stones for future reference.