In Incubus City you take the role of a man during a strange week-long change he occasionally experiences. Overcome with the intense desire to impregnate women, he must roam the streets at night seeking fertile wombs to knock up. During these times, he manifests strange abilities like enhanced strength and hypnotism, but the compulsion often drives him to do evil and places his life and freedom in danger.

Non-linear, multiple paths, 22 endings and 19 beginnings (unlockable New Game+ scenarios that provide player a different origin and set of starting bonuses), own slaves, recruit girls into prostitution, ruin families, and forge a destiny beyond mortal comprehension.