Lammermoor no Shounen Kiheitai

6 boys in the drama club get recommended by their teacher to take an audition for the famous playwright Alphonse Butler's new play. The audition will take place on the passenger ship "Lammermoor".
In the audition the cast have to live as their characters, and are accompanied by threats of punishment.
What is the shocking content of the play "the cavalry boys of Lammermoor"'!?

(Source: GFantasy homepage)