The Scoundrel's Christmas Challenge: Once Upon a Widow Book (Wicked Widows' League Book 29) - Wicked Widows' League, #29

A contest to win her fortune... Lady Winfield, a long-time wealthy widow, is infamous for her outrageous house parties.  While hosting her annual Christmastide gathering, Christiana proposes a new game: a daily challenge of her choice. She will accept the proposal of the man who can best her at three or more competitions by Twelfth Night. Though all agree to the diversion, no one expects the games to include marksmanship, archery, and fencing.
A contest to win her heart... When Lucius, Viscount Bolingbroke presents Lady Winfield with a secret challenge, she can't resist. Will their midnight rendezvous and private contests end in certain victory for one or a dual attraction for both?