.Hack//Legend of Twilight

From Tokyopop: Welcome to The World, the most advanced online game ever created. In The World you can be anyone you want to be, act out your adventure fantasies and through teamwork and determination, you can even become a hero. 14-year-old twins Shugo and Rena just won a contest that lets them play as the legendary avatars 'Kite' and 'Black Rose.' Armed with the power of the Twilight Bracelet, the two must discover what is causing rogue monsters to infect The World and carry on the legend of the .hackers.