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: Denise was driving home from work. Sentence2: She absentmindedly looked out her window. Sentence3: She saw her coworker driving next to her. Sentence4: Denise honked her horn to catch her coworker's attention. Sentence5: Denise's coworker noticed her and waved happily.
Output:
Denise, Coworker