First off you have your book just out there online waiting for someone to steal it. Copyright it. If you dont have the money, poor-man copyright it. Ill tell you how to if you dont know.
My thoughts on:
-The first thing i noticed was basic grammar issues, it makes it harder to read.
-The part when david is getting ready to smoke you jump to bryan being tied up in the trunk, you should go more into depth on how she managed to do this to him. Id find that more interesting.
-If the order of your events and descriptions were changed slighty this would flow more easily.(i could explain more in depth if you want me to)
-Run-on sentences like whoa. Split them up make it more evil if you will. For example,
Id do this. The angel returns quickly with a large tank that, in his teary eyed condition, David cannot read. She leaves the room once again but from the immense pain David cannot focus on her actions. She returns wearing a mask with two short and one long hose wrapped freely around her small shoulders. Davids fright now allowed him to focus on what she held, a second tank labeled oxygen and the first tank only chemical A was recognizeable.
Not that my writing is better, i like your style, its just the sentences and the order.
-The end gets a little confusing but i like the details in the second part over all.
-Again run-on sentences like crazy.
-I like your descriptions but shit you jump around in the story alot. A thesauras would come in handy for you too cause it seems the same descriptive words are showing up.
-You jump around. i like the flashback but you should bring her flashback on while shes hurting David. Like hes screaming and biting on the gag so hard his mouth bleeds or something and her seeing that brings on this crazy flashback of her father which will explain why she does this crazy shit or something like that.
ill continue with the rest later.