When a car accident leads a young couple into their nightmares to an accursed clinic, aborting a foetus demon means life or death to whoever wakes up first.

I am unable to make sense of the story. "leads.. into their nightmares" -- does that mean both of them are unconscious after the accident?
"means life or death to whoever wakes up first".? So ... whoever wakes up 1st lives or dies?
"aborting a foetus demon"? -- and if it's not aborted, what are the consequences, the stakes?? Do both parents die? Just the mother?