Dangerous Games
by Stephanie James, Jayne Ann Krentz

The Devil To Pay (originally published in Silhouette Desire #187, 1985)
Emelina Stratton was desperate to save her brother's life. Desperate enough to ask mafia-chieftain-in-hiding Julian Colter for help. The man, shrouded in mystery and with lethal good looks, said yes. For a price, of course. Emmy would have The Devil To Pay. Especially since she was what Julian demanded in return.

Wizard (originally published in Silhouette Desire #211, June 1985)
Intellectual Sophia Bennett knew what kind of man she wanted: a rugged cowboy. And in Texas they were everywhere! So why couldn't she take her eyes off brilliant professor Max Travers? He was a Wizard in mathematics who surely made love by the numbers. Yet every inch of him—no Stetson, no dusty boots—added up to dangerously sexy.