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: Brian was addicted to soda. Sentence2: He drank at least 10 cans a day. Sentence3: At the end of the month he had 9 bags full of empty cans. Sentence4: He took them to the recycling center. Sentence5: He made enough money to buy another week's worth of soda.
Brian