CAGED - A prisoner to their obsession

"please, I'm sorry, I won't do it aga-" She screamed in pain only to get cut off by another slash from the whip.
"I know you won't doll" Lucian smiled grabbing her hair in his fist.
"but bad girls needs punishment" August cried as she was pushed with a rough force. Alexandar and Elijah smirked.
......................
The only thing that 17 year old August desired all her life was to turn 18 and leave the hellhole she has been surviving in. She had it all all planned out but everything got ruined when they entered and then she realized that it was worse than everything that she had previously gone through.
They.
Alexander, Lucian and Elijah. The three devils who were worshipped by women and envied by men but feared by everyone. They had it all planned out, get married for their business, conquer all big giants but everything crashed when they saw her in their own weddings.
Who she was?? Their brides's sister