The proximity sets off alarms and has him tensing up, stopping short of squirming. This is how close people get to him in order to kill him because not many other people would want to get this close for other reasons, and it puts him on edge.

The soldier takes a deep breath to calm his nerves and dutifully follows along, mulling her words over.

"Uh, I'm- my place, it's- I wasn't expecting guests." He's not one to care about what other people think but all of a sudden he feels like it matters if she sees the booby trap he has to disarm to get in and if she realises he's been sleeping like a baby on the floor.