Devil in Spring by Lisa Kleypas

An eccentric wallflower...

Most debutantes dream of finding a husband. Lady Pandora Ravenel has different plans. The ambitious young beauty would much rather stay at home and plot out her new board game business than take part in the London Season. But one night at a glittering society ball, she's ensnared in a scandal with a wickedly handsome stranger.

A cynical rake...

After years of evading marital traps with ease, Gabriel, Lord St. Vincent, has finally been caught-by a rebellious girl who couldn't be less suitable. In fact, she wants nothing to do with him. But Gabriel finds the high-spirited Pandora irresistible. He'll do whatever it takes to possess her, even if their marriage of convenience turns out to be the devil's own bargain.

A perilous plot...

After succumbing to Gabriel's skilled and sensuous persuasion, Pandora agrees to become his bride. But soon she discovers that her entrepreneurial endeavors have accidentally involved her in a dangerous conspiracy--and only her husband can keep her safe. As Gabriel protects her from their unknown adversaries, they realize their devil's bargain may just turn out to be a match made in heaven...

This book is part of the "The Ravenels" series.
Here are some other books from this series: