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"It's a thriller detective novel where the killer is a woman who lures children through the Internet using initials like A.A & J.J(from A to J in order)and kills them. It's later revealed that the woman's motive was that her husband had undergone vasectomy hence she was unable to have children even though she really wanted to have them and discovered that before he had a vasectomy the man had donated to a sperm bank resulting in the birth of children who were half siblings but weren't aware of each other and who ended up being her victims"