Need to know has this ever been done yet?

My brother said he had a dream that he thinks could be made into a manga if he put a little effort into it but we don't know if this has ever been done before, it happened like this. Two girls one named Princess Veena and we are still thinking of the other girls name. Princess Veena can fuse with the spirit of a wolf and the other girl can fuse her self with the spirit of a dragon. There are times when these two will fight with each other as allies and there are times when they will fight as enemies. We have the title named Mystic Souls but we are still trying to figure out a good synopsis of the manga of how it would go.