Onirism is an action/adventure game where you step into the shoes of Carol, a spirited and imaginative little girl with a bit of a bratty side. One night, Carol is awakened by a mysterious portal that appears in her bedroom. From this portal, a strange creature emerges and steals her beloved Bunbun plushie. Without a second thought, Carol dives into the portal to retrieve her toy, finding herself in Crearia, a fantastical world filled with peculiar lifeforms.