Yoru no Namae wo Yonde

A young girl named Mira lives in the forest with her doctor, Rei. Mira suffers from a condition that causes her to summon darkness when she is in distress. Rei is committed to finding a cure and helping Mira reclaim her former self. Their quiet life is disrupted when Rei's friend visits and expresses a personal interest in Mira's condition, potentially ending their peaceful existence.