I Wanted to Be a Guard, so I Became a Controller.

After the music was lost, humans retreated to ten resonance cities, maintaining their final territory with sound stones and remaining melodies. Sixteen-year-old Rean Saville originally only wanted to become a bell guard, obtain the qualifications to enter the deafness zone, bring back enough sound stones, and keep the inn run by his mother and the residents who had nowhere to go. Until Gray Bell Town lost seven seconds in a bell...