Given the task definition and input, reply with output. In this task, you're given a story (which contains five sentences only). Your task is to find all the characters which are available in the given story.

Sentence1: Peter loved to read. Sentence2: Science fiction books were his favorite. Sentence3: A new book by his favorite science fiction author came out. Sentence4: He counted his allowance to see if he had enough money to buy it. Sentence5: He did, so he went to the bookstore and bought the new book.
Peter, Author