Tokyo Avengers.

The eleventh grade has arrived for a field trip to a music school where everyone plays their own instruments, and if they wish, they can form their own band and ask the teacher to organize a stage for a concert. The music teacher's name is Derek Waiter, and the school teacher's name is Ryuki Imezo.
Ryuki Imezo: Children, please do not distract the students from their rehearsals or their work.
All the eleventh graders and the teacher entered the music building. Everyone scattered, looking around at everything. But Draken, Mikey, and Mitsuya were drawn to you by your appearance and the way you played your instrument.