
I know that some people have dabbled with copying a creature's aether to utilize their attacks and abilities. It's reasonable enough in the setting. That said? You risk having your concept exploded or otherwise meddled with in the event BLU happens canonically. XIV has already proven they don't mind sticking iconic jobs behind exclusive lore (think Dragoons and Dark Knights being so intrinsic to Ishgard's culture, or White Magic/Black Magic being so hamstrung with limitations on who can use them) and there's a greater-than-zero chance that your character could suddenly find itself being impossible (or just highly improbable).
Like others have mentioned, sit tight for now! We'll know in February what other job we'll be getting and you might not have to make it up.
Like others have mentioned, sit tight for now! We'll know in February what other job we'll be getting and you might not have to make it up.