Lilith is a demon that appears in Darksiders and Darksiders II, as well as the Darksiders comic.
History
In the first Darksiders, she is only heard as a voice giving Abaddon the choice to serve in Heaven or to reign in Hell. Abaddon chooses the latter and becomes the Destroyer.
Lilith also appears in Darksiders: The Abomination Vault, being offered a chance to participate in the plan of the hooded stranger. He claims that she has no reason to love Heaven or Hell, and that she should want the chance to reclaim what was taken from her. Lilith coldly declines, stating that whatever was taken is not enough to make her fight all of creation.
Lilith appeared in Samael's domain shortly before the Endwar, offering the Blood Prince whatever he desired for an unknown price. However, he rebuffed her without seeming to even consider it, saying that he desired only her silence. The Four Horsemen delivered a warning to Samael then, to respect the treaties binding Heaven and Hell. When the Horsemen implied that Lilith's presence was due to Samael's proximity to the Dark One's seat, Lilith grew angry and directed them to Abaddon if they wished to warn anyone, as he was the an open proponent of war.
Darksiders II
While Death sought to resurrect humanity, Lilith had hoped to manipulate him into bringing back the Nephilim, the angel/demon hybrids that she created and that the Four Horsemen also were. She took to haunting Shadow's Edge, where she knew the Horseman would come for the demon held key to the Well of Souls. After entering a chamber in Samael's domain and killing a demon that attacked him, Death called out for Lilith as he knew she would be watching. Lilith emerged from pool of magma and told Death he couldn't blame her for hiding as when Death rides, no one is safe, not even her, his mother. Death refused to acknowledge her as his mother which led her to recount her creation of the first Nephilim, Absalom whom from him the rest were formed. Lilith recalled how the Horsemen killed their brethren but only Death showed remorse for the action, which she later refers to as a sin, and reasoned that he didn't throw the amulet in the Abyss as the Council had ordered so that he might restore them someday. Death angrily exclaimed that the corruption was born in Absalom and was now spreading, and she, his "Mother" should help him stop it. He demanded that she hand over the demons' key to the Well of Souls. Lilith told him that Samael kept it, but also that he was gone and the key had vanished. However, Lilith assured her "child" that time, like sin, could be undone and gave him the Phasewalker, which would allow him to go to the past and find the key. All she asked in return was that when Death reached the Well of Souls, he would answer his heart and resurrect the Nephilim. Death walked away without a word while Lilith smiled grimly. After Death killed Absalom and restored humanity, Lilith was seen walking through a dark corridor, where a mysterious figure awaited her. She addressed the being as my Prince, presumably Lucifer, and he asked her about the Nephilim. Lilith didn't know what to say, only for the figure to remind her that the Endwar was upon them, and that instead of giving him the army she had promised, Death had returned mankind to the balance. Lilith resigned herself to her fate and, with a smile, told him that she awaited her punishment. However, the figure told her that this time she would derive no pleasure from it. Lilith was then heard screaming.