Letters in the Dark

Crept down the final flight of stairs to the building lobby, hehe... The cool night air slipped through the glass entrance, but a row of bronze mailboxes beckoned. Squeezing my plump frame into the narrow gap behind the metal bank, I found a loose white envelope dangling half out of slot 204. I hooked my stubby claw on the flap—tug, tug—and pulled it right down into my shadowy crevice. Now I'm sitting on a crinkly paper throne, listening to footsteps click outside on the pavement, completely invisible...