Yurei are spirits in Japanese folklore, often depicted as the souls of the deceased who have not found peace. They are typically characterized by their white funeral garments and long, unkempt hair. Yurei are believed to linger in the physical world due to unresolved issues, such as unfinished business or strong emotions like anger or sorrow. These spirits are commonly associated with traditional Japanese beliefs about the afterlife. In many stories, yurei appear at night and can be seen wandering in places where they once lived or died. Rituals, such as Obon, are performed to honor and appease these spirits, helping them find peace and move on.