Laura's Dad (Missing subplot)? - SPOILERS
I was watching the movie thinking that her dad could somehow fit into a plot with Marina; We know he died and he "would" have been 55, as well as being a psychologist. What if the non-demon Marina targeted Laura based on a possible connection with her Father? She has no real emotive response when Laura tells her anything about her dad which furthermore backs up a possible plot where Laura's father "Could" have been her psychologist (and later killed by Marina?)
He definitely seems to have some role to play in the film other than being a figure of inspiration for Laura to be at College.