Mushishi Temporada 1 Episódio 21

A lady named Aki discovered a green stain on her wedding gown, one year later she gave birth to a boy who, now grown up, has the same marks on his body. It turns out that the boy was originally born not as a human but as some shapeless green blob, which then turned into a human. Her husband asks for Ginkos help yet he is unable to save her son because its the work of a Watahaki.