A Bit of Mistletoe: Regency Seasons, Book 4 (Unabridged‪)‬

Everett Casemore, the very serious Marquess of Berkswell, returns home for Christmas, slightly shaken by the death of an old friend. Determined not suffer the same fate at the hands of a woman, Berks resolves himself to eternal bachelorhood. Unfortunately, both his resolve and his peace of mind are threatened by the arrival of a very pretty, but most unsuitable lady.

Miss Theresa Birkin knows better than most than an error in judgment can lead one down an unfortunate path. If only she'd been wiser when she was younger. If only she hadn't followed her heart. If only she'd met Lord Berkswell long before now.