“Necromancer” by Keith Thompson.

“Madame Theodosia hearkens from the Aeolian islands and is part of a long lineage of necromancers. Growing up in a family with a long tradition of raising the dead, she was uncharacteristically shaken to learn of her barrenness, and in a rather emotional state vowed to give birth, if not to a new life, then to an already passed life. For this purpose she had found assistance in fashioning a steel, pressurised womb in which the souls of the freshly dead were to be trapped and condensed. This gestating entity came to be referred to in hushed tones as The Collect. The expectant mother now unnerves her followers with a detached resignation towards her eventual agonizing death; a necessity to feed her newborn babe in a self-sacrificial fashion akin to a mother spider.”