The Toast of the Town — Alice Chetwynd Ley

FLIRTATIOUS, MISCHIEVOUS, SHE USED HER BEAUTY IN A RECKLESS WAGER...TO WIN A GAME OF LOVE AND REVENGE.

The Whims of Passion
Beautiful and coltish Georgiana Eversley was well aware of her intoxicating powers. She took it for granted that she could captivate any man who caught her fancy, though few men did. But when the handsome young Dr. John Graham let it be known that he didn't care for her at all, Georgiana's hurt pride demanded revenge. And so it was that she accepted a daring warger to prove that she could indeed entice the young doctor and jilt him savagely as well. But Georgiana was unaware of the whims of passion and unprepared for the dark and startling reward of a gambling heart...
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Corgi (UK) Edition:

Lovely Georgina Eversley had half London at her feet. With her red gold curls and her flashing green eyes, she was the tast of the town and the belle of every ball. But Georgy was a high-spirited handful and her younger brother Freddy aided and abetted her tomboyish pranks.

While staying at the country home of their brother, Hugh Eversley, Georgy and Freddy entered on a wager. It concerned their neighbour, the forthright Scottish doctor John Graham, who, unlike all the other men of her acquaintance, appeared unimpressed by Georgy's charms. Her efforts to captivate the man of medicine were hindered by the presence of two of her admirers, Viscount Pamyngton and the odious Henry Curshawe.

And in taking on the wager, Georgy was playing for higher stakes than she realised...