Lyon of the Ton by Emily Royal

Divided by betrayal…united by need…redeemed by love
Wealthy widow Lady Betty Grey conceals a tragic history behind the façade of the glittering socialite. When her scandalous secret is exposed by the man who once broke her heart, she must act quickly before gossip brings about total ruination. Her old friend Mrs. Dove-Lyon offers, for a price, to secure Betty a titled husband willing to marry her sight unseen—then consummate the union within an hour of the ceremony to seal the deal.

Harcourt Martingale, fifth Duke of Pittchester, faces bankruptcy. Still bitter from past heartbreak, he has no wish for a wife. But needs must, and he enters the Lyon’s Den, where titled men sell themselves for a dowry. Unwilling to indulge in the drinking wagers best suited to the young, Harcourt enters a simple game of chance, and wins an anonymous bride who insists that they meet at the altar then proceed to the bedchamber.