Something about this whole story isn't adding up. If the girl was unarmed, why would she come down the stairs after hearing gunshots, when it would be assumed that she would know the guy she was with was also unarmed....?
Plus the whole "moving of one body onto a tarp..." makes me feel uneasy. Like this was premeditated....
Part of me thinks the whole burglarly thing might have been his excuse to hunt some humans.