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: Gus was mixing up some sauce to put on the buffalo wings he made. Sentence2: He knocked over a bottle of hot sauce into his mixing pot by mistake. Sentence3: The result was the hottest sauce he ever tried before. Sentence4: Gus served all his wings to his friends. Sentence5: The sauce was so hot they could not finish them.
Output:
Gus, Friends