only skunks, that search (line 37)
That the skunks are there further reinforces the fact that there are no people around. In fact, they're free to roam the streets because it's so darn empty in the town!
I stand on top of our back steps and breathe the rich air – (lines 43-44)
This mystery "you" (implied in the "our") that's missing throughout the poem makes our speaker seems even sadder. It makes us think that maybe he once had a companion that he now longs for on those lonely nights.