Marcie is tired from another day of hard work but at least she was saving money. Pretty soon she’d be able to get out of there.
Now have Marcie undergo a transformation.
In lots of YA novels like “I am Number Four” and “Shiver” teen characters undergo some kind of transformation once puberty hits. Hey, it happens in real life so why not in a supernatural novel. Try adding the line above and the whole transformation idea as you write about Marcie.