A rather common scenario in adult works but I was wondering if there are any real good series out involving a girl who is in some sense "enslaved" and gains freedom. Doesn't matter how this liberation happens, whether she is saved by a friend, by a stranger, by a crush, by her family, or even saves herself. Also doesn't matter what the nature of the slavery is, whether the girl is locked away and tied up or simply being blackmailed/threatened into doing as she's told whenever her "master" wants. Even better if it's a group thing, where there are multiple girls in this situation and they're all liberated through external help or internal efforts.
My only limiting request is that the characters not be too exaggerated. Though personally leaning in the A direction, I'm OK with moderate busts or even somewhat large if the story's entertaining, but nothing so big it's ridiculous.

Also, one example comes to mind with a blackmail-type partial slavery and a lover saving the day. I don't remember the name, but there is a story I read a while ago. If I remember right, the heroine was dating a relatively weak, geeky guy whom a lot of bullies constantly picked on. They reached a point where the girl was desperate to protect her boyfriend, so she confronted them, and they raped her. They continued to force her to submit to their every whim for some time, until one day her boyfriend came back and saw the aftermath. He embraced her and swore he'd put an end to it. The next day she gets to school and finds all the bullies prostrating before her boyfriend and begging forgiveness. Turns out his father/grandfather is either a company president or some other incredibly influential individual who could destroy each bully's parents' jobs and reputations in an instant; he just didn't like using this against people but when his girl's on the line none of that matters.

OK, found that work. It's a part of Waisetsu Missile by Taropun. The girl wasn't going out with the guy or anything, she was merely a timid classmate of a geek who was being beaten by bullies for refusing to follow their orders. She stepped in to protect him, and the bullies offered to stop harassing him if she did everything they said. She agreed and was made into their personal slave. Things escalated further and further until she was forced to stay in the men's room offering herself to whoever came in when the geek finally found out and came to find her. He wanted to stand up for himself with his own power and to protect the girl with his own power, but for expediency sake he contacted his grandfather, CEO of a huge company. His grandfather threatened to stop doing business with the bullies' parents' companies, which would pretty much destroy those businesses, and when she came to school the next day the bullies were all bowing and begging forgiveness.