Black Sheep by Georgette Heyer (Acceptable, 1968, Pbk, 232 pgs, Bantam Books)

Cover has wear; pages appear to be unmarked but are age-toned. ISBN 9780553103229

Abigail Wendover, 'on the shelf' at twenty-eight…is determined to prevent her pretty and high-spirited niece from becoming attached to a good-looking town-beau and an acknowledged fortune-hunter of shocking reputation. Unfortunately, that means a confrontation with his scandalous uncle.

Miles Calverleigh, the black sheep of his family, is enormously rich from a long sojourn in India, has a scandalous past, and is not at all inclined toward good manners. Miles turns out to be the most provoking creature Abigail has ever met―with a disconcerting ability to throw her into giggles at quite the wrong moment… Could he be Abby's most important ally in keeping her niece from a most unfortunate match?