Instructions: 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.
Input: Sentence1: Charles' father told him it was important to shine his shoes. Sentence2: Charles didn't see why, but he always kept his shoes shined. Sentence3: One afternoon, Charles interviewed for a management position. Sentence4: Charles was hired, but his boss said competition was close. Sentence5: He told Charles he was hired because the boss liked his shined shoes.
Output:
Charles, Father, Boss