Who is Gideon Cross and why is it believed that Christian Grey is losing some of his fans? You have to read both E.L. James' "Fifty Shades of Grey" and Sylvia Day's "Bared to You" to understand.

E.L. James rose to fame for her Twilight-inspired erotic series popularly known as "Fifty Shades." Her works drew criticisms from other writers who were unhappy about her less-than-creative writing style. But the book sales tell a different story. James's trilogy has sold over 40 million copies worldwide. Her trilogy has been labeled "mommy porn" and is believed to have encouraged men and women to explore sadomasochism. A film adaptation is now in the works. Christian Grey, the billionaire BDSM sex dominant, is openly adored by female readers.

Then came "Bared to You" from Sylvia Day's Crossfire series. It was followed by a sequel called, "Reflected in You." Have things changed for Christian Grey's fans?

Within three months, "Bared to You" has sold over a million copies. "Reflected in You" has charted with 82,000 copies sold in the first six days of release. The question is -- how similar are Christian Grey and Gideon Cross?

Here are five things to know about Sylvia Day and 'Bared to You'

1. Sylvia Day is an award-winning novelist who is currently at the Board of Directors of Romance Writers of America.

2. "Bared to You" is Day's 11th novel. It is the first in a series called "Crossfire." Day's first novel, "Bad Boys Ahoy!" was published in 2006.

3. Unlike E.L. James, Sylvia Day received positive reviews for her prose. Her books are said to be "better written," "sophisticated," and "engaging." But Day is also receiving criticisms for a different reason - her story concept is said to be undeniably ripped from "Fifty Shades of Grey."

4. The central characters in Day's series are 24-year-old Eva Trammell and 28-year-old billionaire Gideon Cross. They are, according to Day, not perfect "Cinderella" characters. Day has said in previous interviews that Ana Steele and Christian Grey are presented as flawless characters. In contrast, Eva and Gideon have obsessive issues and "baggages." The Daily Mail also pointed out, Day's books are not centered on sadomasochism. Now, is it just a coincidence that Crossfire has Ana for Eva and Gideon Cross (GC) for Christian Grey (CG)?

5. "Reflected in You" has jumped from the seventh to the second place this week on the New York Times best sellers list (combined print and e-book fiction). It has been on the list for four weeks now.

Crossfire vs Fifty Shades: The readers weigh in

"In my opinion I think it's better than Fifty Shades and it may have to do with Sylvia Day being a seasoned author," notes a reader at Amazon.

"Ms. Day created her own story based on the widely popular E.L. James book, 'Fifty Shades of Grey,'" posts Leslie R. Fear, also on Amazon.

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