Much like the dual role of demonslayer/girl-next-door she plays on tv, Cosmo cover girl Sarah Michelle Gellar has a split-personality sense of style. On days off, her fresh faced beauty routine is sunscreen, light makeup, and pixie-chick braids. But as the star of the hit series Buffy the Vampire Slayer and a vixenish movie actress, Sarah's required to glam it up on the job. And though she claims she's really a "jeans and sneakers girl," party paparazzi shots-and her Cosmo cover photo-reveal that she's equally at home in sexy designer dresses. Pair that with her oft-changing hair color (blond on Buffy, brown as Kathryn in the recent hit Cruel Intentions, and red on occasion) and it's clear that Sarah's style is impossible to predict.