The emerging field of panoramic video generation from text and image prompts unlocks new creative possibilities in virtual reality (VR), addressing the limitations of current immersive experiences, which are constrained by pre-designed environments that restrict user creativity. To advance this frontier, we present Imagine360, a proof-of-concept prototype that integrates co-creation principles with AI agents. This system enables refined speech-based text prompts, egocentric perspective adjustments, and real-time customization of virtual surroundings based on user perception and intent. An eight-participant pilot study comparing non-AI and linear AI-driven workflows demonstrates that Imagine360's co-creative approach effectively integrates temporal and spatial creative controls. This introduces a transformative VR paradigm, allowing users to seamlessly transition between 'seeing' and 'imagining,' thereby shaping virtual reality through the creations of their minds.