Once you have all the necessary items to become an employee, you will then be able to enter Wortten's Office. There you will meet Wortten and be challenged to a cook off. When you go to the Japanese judge, he'll tell you what he likes. Sadly, the choices are randomized, and therefore are not always the same. If you do choose the correct options, the judge will favor you and send his ninjas to attack Wortten instead. Wortten by herself isn't much of a challenge if you use the same technique as you did with the Evil Nun. However, Wortten can regenerate health by eating the ninjas and judges. Use the combination of weapons to get your justice attack faster, which will obviously deal more damage. Keep doing this, since she'll eventually stop bothering you and just go for the ninjas. She is level 17, and can regenerate her health, so make sure you have potions available at the ready. By using your best strategies that you've used on previous bosses, it will help you with slaying Wortten.