Androgynous. Wavy brown hair. Sharp features. Massive amount of letters on it's skin- Cyryllic, Chinese, Cuneiform, Arabic... Also, absorbs magic involuntary.
Has wavy, deep brown hair, brown eyes, average skintone- nothing you'd take notice of. Indeterinate gender. Has a large amount of letters written on their torso- of many alphabets and languages. Slight, short.
Jackie is shy. While confident in the presence of powerful magic (due to absorbing it, giving him/her/it/the borg collective energy), normally they are shy, avoidant and scared.
An enchanted sword. Not your standard enchantment, either- this one is empowered by a Mage's soul, and is incapable of being nullified by Jackie's ability. Knives, vials of poison... Nothing magical but the sword.
Jackie is basically an extremely complex magical sending- created by the Magi as a weapon to be used against powerful magicians. Eventually, the sending achieved sentience- and named itself Jack. Running away, the thing discovered the sword, possessed by the spirit of the original Mage.
Does NOT like most magicians.