Charming the Accidental Suitor by Maggie Dallen

Lord Albright had no intention of falling in love again. But that was before Miss Felicity fell into his lap… Literally.

Was Felicity too old to be climbing trees and spying on her uncle’s visitors? Perhaps. But in her defense, she was so very bored. And besides, she’s well aware there’s a smuggler on the loose in London, and she has her suspicions…
But so does Lord Albright. And it’s a surprise indeed when his stakeout beneath a tree is interrupted by the very pretty, very peculiar young lady who lands on top of him. He has no desire to drag her into a dangerous investigation, but Felicity has a way of sneaking into all the places she should not be—ballrooms, abandoned warehouse, and, as he’s horrified to discover—his heart.

Felicity’s story is the fourth and last novella in the Charmed by Chance series, a School of Charm spinoff, which is best read in order.