Definition: 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: Kay was at work with a Migraine. Sentence2: She didn't have much sick time so she stayed at work. Sentence3: Her friend came and told her to try wearing sunglasses. Sentence4: Kay knew the light made it worse, but she had no sunglasses at work. Sentence5: Kay was overjoyed when her friend allowed her to wear her sunglasses.
Output:
Kay, Friend