Fumetsu no Anata e

An immortal orb is cast onto Earth by an unknown observer with two abilities: it can copy the form of something that deeply stimulates it, and it can return after death. At first it becomes a rock, then moss, then a dying wolf. Taking the wolf's shape gives it movement and leads it to a lonely boy waiting in a frozen village for family members who may never return. That encounter becomes the beginning of a much longer journey. Eventually named Fushi, the immortal learns language, pain, love, and human connection by meeting people whose lives are painfully brief beside his own. At the same time, mysterious creatures called Nokkers begin hunting him, turning every bond he forms into both a source of strength and a possible loss.