Valerie Vambite is a Vampire living in the Crystal Caverns of Gravity Falls She first appears in The Bite That Changes Everything (Episode 15).That Fan-Made Episode She Goes to The Mystery Shack Do Get Some Blood and turns Mabel Into a Vampire and then Valerie Leavs to the Caverns with a Jar Full of Blood and Mabel Attacks Dipper,later He Changes her back into a human with a Spell in the 1 Book.She Is never seen again til episode 26 Called The Vambites Strike Again(Vambites Is Valerie's Last Name).Episode 26 Is the Last Of Valerie.