Calling to the spirits of the dead usually results in either a primal (see Shiva, Thordan, Bahamut) or a voidsent inhabiting the body (see Tam-Tara Deepcroft Hard). While a body can be infused with aether to make it live again, it won't retain the spirit of the deceased and will be just an empty shell (see the quests leading up to Lakshmi), or if the spirit does come back, the body usually fails soon afterwards and dies again anyway (the alchemist 1-50 quests). True necromancy is exceedingly rare in this game.