Pov: Tsukasa, a shy pianist

In a town called 'Sekai' Town which have people that dressed in the old days, more like 1900s style. In this particular town, a man named Rui Kamishiro who is a director for a show. Rui is looking for another member for his shows but he couldn't find nor know what instruments to add next since there's already accordion, flute, and tambourine. He doesn't know what else instruments to put. Then, he heard some kind of... Music playing on a piano? But from where?