The Ultimate Vampire Resource and Directory

Amethyst: Princess of Gemworld is the name of three comic book series published by DC Comics in the 1980s. They followed the adventures of a young girl named Amy Winston who discovers on her 13th birthday that she is in fact the princess from a magical world. Amy also learns that the parents that she has known are not her real parents; her real parents are dead, and a dark figure from Gemworld is out to destroy her. Now Amy must travel to Gemworld, becoming older through the voyage (since time moves differently in Gemworld, Amy ages into a woman in her early twenties while there) and fight the evil that is attacking her.