When you get here, there will be a cutscene where the Heroine and hero Meet Bogard and Cibba, read and watch carefully, the Hero will go outside and see The Granz Realm Airship, if you are the Hero, you will see Dark Lord, a soldier and a strange man called Julius. You will attack Dark Lord, He'll injure you then Julius will push you back into the cathedral and the mirror will break, the Heroine will go on the airship peacefully.
You'll wake up in a bed, Lester will talk to you about what happened, how the Heroine will be on the airship, you need to go to the Cathedral again. Talk to Devius and he'll ask you to release his birds in his room, (the left room of the inn). Now go back to the Cathedral and you'll hear his plan, the airship will dock at Westlake and get on the ship. You need to go through Gaia Cave to get there though. Then you'll be given Wisp. After a cutscene, you should go to the south of Wendel then go west to Mushboom Forest.
You'll appear in a room on the airship and witness a long cutscene with Dark Lord and Julius and a maid called Marley. Marley can tell you things about herself and other important characters you've met. Select End to continue with more cutscene. When you finally get control of your character talk to Marley and she'll tell you about some books in the room. Go read the middle book on the table. Talk to Marley again and then go read the book again, then check out the closet.
Another long cutscene takes place until eventually you'll be alone with a soldier who is really Bogard in disguise, he reveals his plan to cause the ship to make an emergency landing so you can both escape.