Lacrima is a sickly girl living with her alchemist parents on the edge of the Dark Forest in a village called Amber Stone. Her parents are always busy preparing medicines for the village, and they always give her the same answer when she wants to help: you need to rest. Lonely and restless, she finds solace in the Dark Forest itself, where she has made friends with Nox, a mysterious owl creature, and Angis, a non-human alchemist boy who blushes easily. When she overhears her parents discussing a moonflower — a plant that only blooms in the Dark Forest on full moon nights and that they urgently need — she slips out after dark to find it herself.