[John F]

I'll nominate The Duke and I by Julia Quinn.

From Amazon (possible spoilers):

Spoiler:

Can there be any greater challenge to London's Ambitious Mamas than an unmarried duke?—Lady Whistledown's Society Papers, April 1813

By all accounts, Simon Basset is on the verge of proposing to his best friend's sister—the lovely and almost-on-the-shelf—Daphne Bridgerton. But the two of them know the truth—it's all an elaborate ruse to keep Simon free from marriage-minded society mothers. And as for Daphne, surely she will attract some worthy suitors now that it seems a duke has declared her desirable.

But as Daphne waltzes across ballroom after ballroom with Simon, it's hard to remember that their courtship is a sham. Maybe it's his devilish smile, certainly it's the way his eyes seem to burn every time he looks at her . . . but somehow Daphne is falling for the dashing duke . . . for real! And now she must do the impossible and convince the handsome rogue that their clever little scheme deserves a slight alteration, and that nothing makes quite as much sense as falling in love.

You've watched Bridgerton on Netflix, now read the book!

Available at libraries everywhere (except where it isn't).