Marcus regained mobility as the demoness fled the scene, satisfied with the impossible challenge she posed to the man-child. She gave Marcus what appeared to be a contest, if he could resist the needs of the flesh for three days, then he would stay human, though orphaned and stuck as an adult. Sadly, Michelle's challenge was as twisted as her corrupted soul.
She increased Marcus' sex drive to unusually high, though still human levels before she pleasured him. That act pushed Marcus a slight way toward becoming an incubus, a male sexual demon. By becoming a fraction of an incubus, Marcus was soon to develop a supernatural lust, one impossible to resist for all but the most strong-willed mortals. And Marcus, deprived of a childhood where he could forge such a will from experience, was not so equipped.
Marcus stood up, aware of the new strength he possessed from starting toward demonhood. His erect cock, altered and made larger by his new curse, still cried for release. A small part of his mind called for restraint, but it was being slowly drowned out by a demon's libido.