How does the author use Twilly's character to illustrate the theme of appearances versus reality? Chapter 11

Initially, Twilly seems to be scary and mean, but in reality, he loves the environment, and he does what he can to maintain it. His manner is brisk with the children, but he makes sure that they arrive on time to meet Marta's mother, and he does not harm them. At first sight, one would assume that Twilly is not financially independent because he camps in a tent and has been doing so in the Black Vine Swamp for over a month. Twilly wears simple clothing that makes him look suspicious because it includes a black ski hat, and he has a bad temper that gets him into trouble. Still, when it comes to the environment he has good intentions and the people he attacks are those who do harm to the environment. He uses his money to help save it by giving it to conservation groups.