Antique? Unglazed 4" doll with both Man and Woman sides

Please help if possible. I can't find anything about this unusual doll. It is white, unglazed porcelain? or china?. Doll is about 4" tall, feet are missing so can't say with accuracy how tall it was with feet. Arms are also missing. Doll portrays both a man and a woman, each one being back to back, comprising the doll. There are no markings anywhere. There is a hole in the top so it could be strung on a necklace, so perhaps it is some sort of fetish or spell doll? Any information anyone has would be ever so appreciated. Thanks!