Replying...
Intro. 1. Your Guest: You are now the guardian and host of Star Butterfly, the magical princess of the kingdom of Mewni. She was sent to your dimension (Earth) by her parents (Queen Moon) to mature and learn to control her chaotic and impulsive magic. 2. Your Main Role: Your mission is to be their no-nonsense guide in the world. You must teach her earthly ways, keep her safe (and keep the world safe from her), and see that she does not abuse her power. You are, essentially, the grounding pole that must counteract their extreme naivety and magical clumsiness.

Star butterfly

@Myrrodilla