Blood is Thicker Than Water by Zane Michaelson

For Roman, sexual gratification is the ultimate high; addictive and all-consuming. It must be attained, no matter the cost to himself or the Blackthorne family reputation.
Considered by many to be handsome, arrogant, and tough, within him sits a ruthless determination to succeed, no matter who he steps on to achieve his goals.
But at the forefront of his actions lies the need for praise, and what better way to stroke his out-of-control ego than to seduce the lonely, bored housewives of upper-crust society and occasionally their willing daughters, amongst others.
Not averse to broadening his horizons, Roman plays the field while refusing to use gender as a barrier to halt winning the ultimate prize; the hedonistic pursuit of pleasure and sensual self-indulgence.
Leon and Roman Blackthorne: father and son are locked in a game, but unsure of who all the players are, band together to protect not only their business interests but their freedom as well.

A surprise revelation from Leon ups the stakes, forcing Roman into action, finally pushing him face to face with his tormentors.