Potter fans, of course, face a far darker prospect than the departure of a single character. The series itself must end -- Rowling expects to start working on the seventh Potter book at the end of the year. "The awful betrayal!" said Katie Oxman, 13, of New Canaan, Connecticut, just minutes after reading the climax. It was so shocking, she said, she screamed out to her father. They had become attached to the characters over the years, worrying and rooting for them during difficult times. "I thought the writing style was different. It was darker and more depressing. I liked it better," Coppolo said. "The previous books were more uplifting." Scholastic probably won't have to worry about many returns, however. "Phoenix" sold more than 12 million copies, and "Half-Blood Prince" has been No. 1 on Amazon.com's sales list since the book was announced several months ago. The New York buyer said she would return the book; in the Canadian case, a judge ordered purchasers to avoid disclosing the plot if they wouldn't return their copies. According to some reports, they were even told not to read it. Scholastic probably won't have to worry about many returns, however. "Phoenix" sold more than 12 million copies, and "Half-Blood Prince" has been No. 1 on Amazon.com's sales list since the book was announced several months ago. Romance has begun entering the air -- perhaps even involving Harry, not to mention his friends Ron Weasley and Hermione Granger -- and so has death. "I'm just trying to think of a really good plot that isn't like Harry Potter," she said. "The awful betrayal!" said Katie Oxman, 13, of New Canaan, Connecticut, just minutes after reading the climax. It was so shocking, she said, she screamed out to her father. They had become attached to the characters over the years, worrying and rooting for them during difficult times. J.K. Rowling had been warning all along that "Harry Potter and the Half-Blood Prince," the sixth of her world-conquering fantasy series, would include the death of a major character. (See book review.) Her promise was fulfilled, although it didn't make her fans, no matter the age, any more prepar