He was her father's best friend. She was never supposed to want him.Cora Hale is twenty-one, broke, and out of options. When her scholarship falls through, her father arranges the only solution — move in with Declan Pierce, his oldest friend. A Chicago penthouse. Free rent. A safe place to finish her degree.Declan Pierce is not safe.At forty-two, he is cold, controlled, and meticulous. A corporate liquidator who dismantles companies without flinching. He sets strict rules for the girl now under his roof — curfews, restrictions, boundaries. Cora tells herself his intensity is paternal. She tells herself the way he watches her from dark rooms is protective.She's wrong.Declan has been burying a forbidden obsession since her eighteenth birthday. Three years of distance. Three years of control — shattered the moment she walks through his door.Now she's in his territory. Every rule he enforces is not a wall around her. It's a wall around him. And walls don't hold forever.What follows is consuming, dangerous, and unforgivable. A secret that will destroy the only friendship he's ever had. A possession so absolute that when her father discovers the truth, there is nothing left to save.Full-length standalone taboo dark romance. No cliffhanger. Dark HFN ending. Book one in the Penthouse Sins series.Content warning: 21-year age gap, dad's best friend, extreme possessiveness, authority and discipline, praise and punishment, explicit content, morally dark themes.