There's pampered girl, who is clueless about the outside world, and a guy (can't remember how he is related to the girl)
but there is another girl that looks exactly like the pampered girl (prostitute?), and he has sex with the lookalike
I remember at the end because the girl was clueless about the world the lookalike tricked her and sold the pampered girl off to a brothel,
The guy finds her in a brothel having sex with some men, the pampered girl was airheaded so she was happy saying she learned alot

The guy may have been her father or caretaker

The overall plot was something like this;
Guy is overprotective of a girl, and has sex with a lookalike of the girl, the lookalike tricks the girl and sells her to a brothel, the guy finds out and finds the girl in a brothel
This all happens in only 1 chapter

I have forgotten alot of the details, so my description may be slightly off, so if you know anything similar please tell me

Thanks