How is the doctor characterized?

The Doctor is characterized as a fat, complacent man who is not from the same race as Kino and Juana, he refuses to treat Coyotito for a scorpion sting when Kino and Juana cannot pay enough. However, once he learns that Kino has found the Pearl of the World, he treats the healed Coyotito after leading Kino and Juana to believe that Coyotito may suffer unseen consequences from the bite. Seemingly interested in stealing the pearl, the doctor is not of the same race as Kino and Juana, and longs for his days in Paris.