Its a big mystery in the plot so far, in fact i dont think the game revealed very many of the types of mystics it features in its gallery. I guess the devs like to hold things back for future plot developments (though ive no idea what kind of roadmapping they do, i think they as a style of dev team do things on the whim as we keep getting new characters whilst older ones have now gone for years neglected in the gallery scenes or made a single cameo and have never been seen since that i recall despite being undisputed mystics such as the dark elf loli or the mermaid at the pond). Anyway still need to play this latest update and will do so once i get the time as i hear there is yet another new girl been added because of course there is lol.