Black Jack no Yuuwaku

The billionaire's bedroom bargain...
Jack Maguire was turned away from his father's house and has never forgotten that day--or how much he wanted his stepsister, Sally. Now a billionaire tycoon, by a twist of fate Jack's inherited his father's property-- and has an opportunity to get revenge....
Jack has a bargain to make with Sally, who has grown into a beautiful, desirable woman. She can keep her beloved house...if she will be his mistress on weekends!

(Source: fictiondb)