With the faint glimmer of magic about him, Snape isn't possible for Peter to see in that amount of shadow, not exactly. But something about the evening air- when did it get so dark?- clearly rattles him, if Snape watches closely. He stops working quite suddenly, glances up and down the street- it's the dogs, there are no stray dogs- and then gathers the trowel up neatly and climbs without ceremony to his feet. He brushes his knees off, puts his hands on the small of his back as he arches slightly, stretching, and then turns on his heel and moves at an even clip into the house.

The door shuts neatly behind him, and locks.

Inside, Peter leans his back against the door for a second, getting a few deep breaths before going to get his gun. He carries the thing into the kitchen, setting it down on the counter as he goes to wash the dirt out from under his fingernails. Normally he isn't quite so casually armed in his own home, but you don't do this for as long as as Peter has without developing and relying on some fairly aggressive professional instincts.

After that, it's the kettle, and the curtains, and a little low lighting in the kitchen.

He prepares the cup in its' saucer, flicks a kitchen light on, but then walks right away into the living room to sink into a seat in there, in a corner of the room where he can see every window, every entrance, including the front door through the hall.