The Dark Lord's Defence Attorney

The Archduke of Sin has finally been defeated. All the kingdom rejoices as he is brought to justice in chains by the great hero Brielle the Bold. Now, he will surely face punishment... but first he'll go to trial. And you? You're the unlucky public defender whose name came out of the hat to defend him. Since all his assets were seized, he has no choice but to rely on you. And he seems pretty sure of his innocence. Was this all a great big misunderstanding?