Isaac and the Black Sword Knights are responsible for training the Maihama army. While he's in Maihama Isaac gets to know the new crown prince of Maihama, a young boy named Iselus.  Iselus respect looks up to Isaac and respects him.
At a party for the crown prince's birthday, assassin's make an attempt on his life.
What do you mean?
Was soll das heißen?
¿De qué estás hablando?
– Comment ça ? Expliquez-moi !
– Shiroe !
Che vuoi dire?
Como assim?
— Я не понимаю. Объясни нормально…
— Господин Сироэ!