If you want to write an erotic romance, whether historical or contemporary, these are a good place to start your study.
Secret Pleasures by Thea Devine is a good example of her erotic romances. She makes a point to use language to convey the emotions of her characters, to make you feel the things they're feeling. And despite all the heat, there's also a story to go along with the sex.
Hellion by Bertrice Small shows why she's the queen of erotic romance--a subgenre she began years ago. She's not afraid to go beyond normal comfort zones, to push the boundaries of sex for her characters and for her readers. More erotic romance authors should study her work.
All through the Night: Tales of Erotic Romance has stories from Thea Devine, Lori Foster, Suzanne Forster, and Shannon McKenna, all superb erotic romance authors in their own rights. Forster has been doing hot contemporary romances for years, and Lori Foster is on the verge of superstardom herself. All these authors are great at turning up the heat as well as at telling a story readers want to read. And that's what it's all about.
The Lover by Robin Schone is another spectacular example of erotic romance. She's not afraid to do a little homework on the historical aspects of her story, and I don't just mean for the setting or wardrobe. She also creates complex characters in her books, making for some intense reading.