The Sinner — Madeline Hunter

Wearing nothing but a man's nightshirt, Fleur Monley woke to find herself in the bed of England's most charming and reckless libertine. But it was a stray gunshot, not passion, that put her at the mercy of a man as infamously handsome as he was famously talented in the arts of love. Believing herself immune to any seduction, Fleur thought herself perfectly safe to make him an offer no ordinary woman would dare make: half her fortune for the freedom she would gain by being his wife -- in name only. Desperately in need of funds, Dante Duclairc could do worse than the "white marriage" proposed by this idealistic beauty too naive to know the danger she was in. But the rashest thing he ever did was tell himself he'd be able to resist the invitation to sin that this sensuous innocent would arouse at every turn -- or that he'd be able to protect her from both the ruthless enemies that sought her ruin...and his own dangerous desire.