Poupelin was a fairy who was enlisted by Queen Badiane for the purpose of gathering children from around the world. She promised them that she would lead them to a utopian realm where all individuals would live contentedly. However, in truth, her intentions were far different; she aimed to imprison these children within Dream Coffins and harness their dream energy to fuel the Black Dream Hole. Despite his status as the fairy king, Poupelin appeared to be the head of this operation.
Sailor Uranus ultimately put an end to Poupelin's reign by destroying his flute with Space Sword Blaster. As a result, he transformed into a blue bird and flew away. According to Wikimoon.