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.
I investigated it before, 
but it's nonfunctional, right?
Wir haben sie schon einmal untersucht,
aber sie funktioniert nicht.
Lo investigué antes, 
pero no funciona, ¿verdad?
Je m’y suis déjà intéressé,
mais il est hors service, non ?
L'ho già controllata, 
ma non funziona, o sbaglio?
Eu investiguei antes, 
mas não funciona, certo?
Я уже изучал это место,
но оно нам не походит.