The Tiniest Invaders free short story online

Over the millenia earth has been visited by a plethora of travellers. They came, they saw, took snapshots, gathered biological samples, and went home. Only one race of aliens liked earth enough to stay, until now. When a roach, that is more than it seems to be, is found in a bathroom the question isn't "Do they come in peace?" But rather, "will they go in pieces?"