Cicero is a Dark Brotherhood member who holds the position of Keeper, the person who cares for the Night Mother's corpse. He dresses like a jester and is first seen transporting the Night Mother's coffin to the Falkreath Sanctuary.
He slowly lost his mind after completing the assassination of a court Jester, who created a desperate bond with him as he slowly died; this infected Cicero with madness, causing him to effect the personality and garb of the Jester. This has contributed to his growing fanaticism in the position of Keeper, wherein he is the caretaker of the Night Mother's remains. He is obsessed with the fact that he apparently will not be chosen to become the Listener by the Unholy Matron whom he serves so diligently.
Cicero vehemently questions the leadership of Astrid and creates controversy and then chaos in the Sanctuary.
He is involved in the Delayed Burial quest.