Lilith has Cambion Conception but I haven’t beaten?
I noticed that I have Cambion Conception on Lilith, (not on the character select screen, but in the actual game) but I haven’t fought ??? as Lilith yet. Does anybody know what is going on?
As explained on the Binding of Isaac wiki,
Lilith's starting items are the Box of Friends, Incubus, and Cambion Conception.
Cambion Conception is just one of her starting items. This items works well with her other starting item (Box of Friends), which duplicates each of your familiars.