Twi-hard
n.— «The most recent “Twilight” book sold an astonishing 1.3 million copies in the first 24 hours, and fans—also known as “Twi-hards”—stay up all night to attend the books” midnight release parties at bookstores across the U.S.» —“Interview with a vampire’s director” by Thomas Rogers Slate Nov. 17, 2008. (source: Double-Tongued Dictionary)