This work presents a novel virtual vehicle based decentralized coordination framework for Connected Autonomous Vehicles (CAVs). We explore the idea of CAVs being capable of positioning virtual vehicles to share their intended maneuver as well as request cooperation. This framework has potential to inspire versatile solutions and provides an intuitive interface to interact with reactive and unconnected vehicles. In this context, a preliminary coordination policy is proposed and tested on a three-legged single-lane roundabout. Simulation results show that the presented solution performs outstandingly better when it leverages the freedom at positioning virtual vehicles that our framework provides. Furthermore, the performance degradation resulting from mixing CAVs and unconnected cars is observed, and coordination assessment under this circumstance is discussed.