Meg Cabot's Princess Diaries series made her queen of teen lit; alas, the all-grown-up heroine of Size 14 Is Not Fat Either, 29-year-old Heather Wells, is mostly just a royal pain in the ass. A teen-pop star-turned-assistant dorm director at a fictional New York college, Wells splits her time between downing Dove bars and solving mysterious campus murders. In this installment, a cheerleader's severed head is discovered in the cafeteria. A queasy mix of chick-lit fizz and a CSI plot doesn't alleviate the two-dimensional characters and mile-away conclusions. Perhaps Cabot should just stick to tiaras.