Neither, It's a relatively large mana crystal resembling a pearl(color depends on magic type) lodged between the occipital lobe and the cerebellum. For example, mine is a deep, shadowy, abyssal black with an empty feeling aura. Other examples I can give is @Neosaiyan7 who I can only assume has a very similar color to mine tho they would have a more void-ish black that offers a very deadly, almost warlike aura, compared to my shadowy abyssal black. And then there is @Abdalla1234 who, if I had to guess, has one colored a vast, purplish color that gives off a hallowed, free-feeling aura. I'd name more but I'm still getting to know everyone here

Magic is stored in the bone marrow.

.....I don't think this is relevant to magic at all.....

Magic is stored in the balls

(im a girl…)

@Abdalla1234 But did my description slap or what? 😏

@Ragnaarthered96 yeah. Right in between the occipital lobe and the cerebellum 😂

What @Ragnaarthered96 said does sound true, very convincing examples as well.