You’re not off base. You’re right on target. I was trying to find the right mentality for part 4, and you have pushed me in the right direction!! I am appreciative!! Truly!
Her and the monster are opposites. She physically cannot be in the dark…it’ll drive her insane…knowing that she’s vulnerable. He can’t be seen in the light, as he is utterly horrifying.
What did he do to deserve being her slave? That’s a question that’ll probably never be answered