I Get Sad

Emerson Alder lives in a world where the human country is surrounded by walls. Why? To keep them safe from the mystical creatures outside the wall that could hurt them. Until one day, a sickness starts sweeping through the land. Emerson's twin sister and best friend are affected, and Emerson is at a loss for what to do. Then, she meets someone, and decides to begin aa quest to search for the cure; the only problem is that it's outside the walls that she's lived in her entire life. Will she be able to find the cure in time? Or will the monsters outside the wall get her?