Ariem is an anthropomorphic horned sheep-like being who guards the Reverie and resides in Reverie Haven, her home. Female horned sheep have horns. Ariem mentioned she was created by multiple creators but doesn't explain who they are. She is commanded by her creators to only allow people she thinks are noble and have good intentions to use the Reverie's powers. Describing herself as a "Dreamweaver", Ariem has the ability to Dreamweave; an ability which can be used with a Dream Orb.