Her Reluctant Lord by Sue London

Miss Agatha Chase has more than enough problems simply keeping her household together, with three younger brothers and one aged servant. Now a great-uncle she’s never heard from before has offered to sponsor her for a Season in London. She is far too old for such frivolity, but everyone tells her that you don’t say no to a duke!

Laurence Garner has unexpectedly inherited his brother’s title, Viscount of Rothering. He’s a man of honor, but the tiresome duties of nobility chafe for a man used to the open sea. And now he’s squiring an insipid miss around London as a favor for a friend! If only something exciting would happen.