One of the Pure Color Six Kings of the Accel World and leader of the Purple Legion Aurora Oval. She and Red Rider were said to be lovers and she hates Black Lotus for killing him.
Thorn along with the Kings of Pure Color attained level nine and decided to create a treaty that separates their territories and disallowed fighting amongst each other to obtain level ten. She was with the other kings during a meeting where she watched Red Rider get killed by Black Lotus.
She holds one of the 7 Sacred Treasures of the Accel World, the Tempest.