Who is Dr. Booshy from Midaq Alley and what is their importance?

A roving, self-trained dentist, Booshy dresses incongruously in a cloak, skullcap, and wooden shoes. He learns his trade by apprenticing to a dentist in the Gamaliya district and becomes sufficiently proficient to set out on his own. He is known for inflicting incredible pain and blood loss during extractions, but offers deeply discounted prices. Booshy rents a flat from the miserly widow, Saniya Afify, who, in anticipation of getting remarried, asks him to extract her teeth and replace them with a gold plate as soon as possible. Somewhat later, Booshy and the filthy cripple-maker Zaita, for whom Booshy solicits clients, are arrested stealing a gold plate from a recently deceased corpse and are jailed for it.