Boy Toy — Rena Marks

Nina has been taught to lessen emotional attachments. A necessary skill to have when a woman intends to stay single forever, with one goal in life -- to train men as Boy Toys.
 
A century-old curse haunts Tristan. For one month out of every year, his birth month, a woman who wears his birthstone pendant can control him sexually. He's grown to hate the women who hold the reins over his life. But Tristan falls hard for sexy divorcée Nina and knows she's the one for him. His only problem is to convince her of this.

Until a new issue arises. His hated pendant falls into the hands of the woman he loves.