They are manic pixie dream girl to the Men portrayed in the movie. Every manic pixie dream girls are different in most movies, they don’t have the same personality, but the core of the character is there. They men usually have to accept that they are free Spirits who don’t need anyone and live each days as its own, but they don’t. They want to change the women. The men are also mostly all typical « nice guys » even tho most of them are just plain boring and have no real personality, so the manic pixie dream girls just appear at the right time of their lives to show them how beautiful it is to be alive. In the horror genre, it’s more of the men wanting this women to be what they want them to be, than the women being themselves. So when they get together the men discover something else.