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.

Example Input: Sentence1: Ava needed a root canal badly- she was always in pain. Sentence2: But she was terrified of dentists! Sentence3: Finally the agony drove her to make an appointment. Sentence4: The dentist was very kind when she arrived, and put her at ease. Sentence5: And to her shock, the root canal didn't hurt one bit!
Example Output: Dentist, Dentists, Ava

Example Input: Sentence1: Rachel was riding her new bike for the first time. Sentence2: She was excited to try it. Sentence3: She took off the training wheels and hopped on. Sentence4: As she got on, she immediately lost balance and fell. Sentence5: She scraped her knee but thankfully it was benign.
Example Output: Rachel

Example Input: Sentence1: I hate my boss' scheduling practices. Sentence2: She schedules meetings within twenty minutes of closing time. Sentence3: They always go overtime. Sentence4: She never credits any of us with overtime. Sentence5: I've begun the search for a new place of work.
Example Output:
I (myself), My boss