Rachelle is a member of the Rinjoh League Elite Four, specializing in ghost-type pokemon. While other members of the Elite spend time accepting challenges and running administration at League Headquarters, Rachelle prefers a more hands-on approach to her daily tasks, making her difficult to both contact and locate.
There is tension between her and League Champion Joel due to her firm belief that the League should protect its citizens though overt action and not just administration. Rachelle created the RPS to help her realize this ideal when League politics obstructed her.
They are ghosts! You can't see them due to their being invisible!