The Snake and the Lion

Amber Drulard or Amber Riddle starts her by years at Hogwarts. Her parents were killed by her parents cousin, Voldemort. She is a direct descendent of Merlin himself. She's best friends with the Golden trio and joins them on their many adventures. But what happens when the son of a Deatheater falls for her in her later years? What hapens when they are on opposite sides?