Out of its picturesque art style, that screeching sound and flashing silhoutte took me to the edge of my seat (and I had to play cheery music afterward :'D).
I get the impression that the complete story of event/"what's really going on at that apartment??" is splitted into tiny clue in MC's interaction with other attendant, but still a mystery as I recently only get (a bit spoiler) the "Jacob abduct me" and "Carter's contact to the alien has disillusioned me" endings.
And it's said that there are 3 endings...so, dare for a walkthrough to other ending? ;)