Here is the premise:
Story is written from a young woman's perspective. She is barely making it by driving Uber and Door Dash. She has a decent body/face but fairly obvious low self-esteem. She is not dating anyone and the last few guys she met on dating apps turned out to be losers with no desire for commitment.
She reads an ad on Craigslist (Is that a thing anymore? maybe some other site where people can put weird ads or start the timeline earlier before it shut down)
"Wanted: Girl for experiments. Must be healthy, and over 18. Safety is not guaranteed. 50 an hour."
She laughs.
She has seen ads for strippers, nude models, nude housecleaners, nude lawnmowing services, prostitutes, and even guys wanting to set up gangbangs.
She's never answered them. She isn't a prude but she just had no interest.
However, there is something about this ad that piques her curiousity simply because of how bizarre and brief it is. What kind of experiments? She pictures a mad scientist in a white labcoat trying to harness lightning bolts to power his infernal machine like in science fiction.
She contacts the person on the other end. She writes several questions and a little about herself (but not her home address/real name). He provides an adress and a time and nothing else. He doesn't ask for a picture, or provide any details.
The first chapter deals with her being apprehensive, nervous and driving there twice before the time just to see what kind of place it is. It isn't a business or labratory. It is a brick building with no signs out front. It appears to have been a clothing store that was abandoned 1980s.
SCENARIO ONE:
The first experiment (whatever it is) is really not that bad and she makes 100 bucks. It wasn't much but it was over pretty quick. WE could even say she was knocked out for it, so she felt like she walked in, got undressed and walked out.
The doctor is creepy/strange but when she jokingly asks where his white labcoat is, he puts one on.
Due to her low self-esteem she has this sort of "why not" attitude about this entire thing. She is on the pill and thinks that if the guy tries something with her - that she'd really not mind.
The experiments could get increasingly weird. I don't know and I am looking for ideas. Could be as over the top as transformign her into a bimbo with huge tits/puffy lips, or even ahuman dog, or it could just be brutal/strange/freaky experiments to see how much electricity she can withstand.
It could also be that whatever happens, as she survives and is altered physically by each experiment, she is altered mentally as well by an increased confidence and growing self-esteem.
"If I was ever kidnapped and the guy tried to torture me, I'd probably ask him what else he has, because all of this has already been tried on me."
"Yes, yes, Mrs. Prescott. The subject will lie back and be silent now."
SCENARIO TWO:
Same as above, but she knows the person who wrote the ad. She never got his real name, he never got hers. She doesn't find out until she arrives
It could be her father - who is a brilliant researcher, and this is his part time job. Her mom doesn't know he does this.
He promises her 100 an hour if she'll assure him she won't tell her mom.
"Wait, you still want me to do the experiments?"
"Well, you need the money and you were going to do them anyway. What is the difference?"
Could be a former school mate who had the hots for her but she rebuffed him. She's forgotten or never even realized how obsessed he was with her. Her low self-esteem prevented her from even imagining someone would think that much of her. He still jerks off to her yearbook photos. The experiments could be similar, but along perhaps a darker path of retribution or alteration towards making her love him.