Tenshi, Ei-chan, and Shiratori all attend Kawagoe Academy. One day, they get pulled into the orbit of former conductor Haruo. He drags them into his newly founded boys choir where they suddenly find themselves performing a song in front of an audience!

You're kidding, right?
تمزحين، صحيح؟
Soll das ein Witz sein?!
Lo dices en broma, ¿no?
Estás de broma, ¿verdad?
C’est une blague ?
Scherzi, vero?!
Está de sacanagem?
Ты шутишь, что ли?