Once ruler of the sixth level, Malbolge, herself her position as its ruler quickly fell by the wayside. She served as a consort to Moloch who was Baalzebul's viceroy. As a result of Molouch's defiance she found herself deposed and placed within the court of lord of flies and as her replacement the hag countess was given ruler-ship as a result of the Reckoning of hell.
Lilith likely counted herself lucky at first when she found out that Greyon had gotten exiled along with his most loyal consort Cozbinaer. She is loyal to the lord of flies but that loyalty has dwindled severely! The ruler of the seventh level has no respect for her insight, considers her wisdom in any matters of war or politics to be foolish and has on several occasions given her to other devils to placate them and done several things to her without a damn care.
Not taken form the following source: http://en.wikipedia.org/wiki/Lilith_%28Dungeons_%26_Dragons%29