Ginko arrives at a house where a sick green boy is.  The mother tells him of how she once discovered a green stain on her dress and of how she gave birth to a larvae like things much later.  Ginko tells them that their son is a mushi that killed their true son and took his place.  He kills the mushi but allows the couple to raise the other kids as long as they promise to kill them before they can release their spores.  He returns a couple of months later to the house to find that the children have grown intelligent and have talked their mother into helping them survive.