What happens after you defeat lucian in Fable 2?

Answer 1

Not much, any unfinished quests or buisness, or something ya wanna do, like open all the Demon Doors, find all the Silver Keys, etc. etc. can be done here. Other than that, the game has finished, really.

Answer 2

After the debt is paid off, you still need to find every treasure in the game to complete it.

See the related question for hints on what to do after you get every treasure.

Answer 3

After you do the final quest, you can complete the rest and manage your relationships, money, power, weapons and much, much more!