Forever, a romance imprint of Hachette Book Group, announced Tuesday that it had signed 32-year-old Meredith Wild, whose "Hacker" erotic series has appeared on numerous best-seller lists.

Forever is reissuing the four current "Hacker" books as e-books on Tuesday and as paperbacks on May 12. The fifth and final book, "Hard Love," is coming out in September. Wild's agent, Kimberly Brower, said the deal was worth $7 million.According to Forever, the series not only has sold more than 1 million e-books, but also around 200,000 copies in paper, a rarity for self-published works.

Fans of "Fifty Shades of Grey" may recognize the "Hacker" narrative: Recent Harvard graduate and Internet entrepreneur Erica Hathaway falls for controlling billionaire Blake Landon.