The Spider is the Ringmaster. He had a web of 'performers' that he controlled, his artists. He had a lost daughter. There were people who wished him harm. The Spider was the Ringmaster.
Who is Petter at the end of the story? By the conclusion, he was an extraordinary man who wanted to live an ordinary life; he wanted to be ordinary. I don't know if that could be true. Petter always lived life in a unique way, due to his abilities and manner of thought. Though, his extraordinary life has been damaging. Can he be average now? He says it is what he wants. It is left up to the reader to decide what the character will do.