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: Consider Input: Sentence1: Marcus was playing his guitar at school. Sentence2: His friend Matthew approached him and asked about the music. Sentence3: Soon they were in a heated conversation about their music tastes. Sentence4: The duo decided that they should collaborate on some music. Sentence5: The resulting album was very popular with all of their friends.

Output: Marcus, Their friends, Matthew

Input: Consider Input: Sentence1: I was having trouble finding my comfortable slippers. Sentence2: I looked everywhere for them. Sentence3: I found them on my wife's feet. Sentence4: She told me she found them in the living room. Sentence5: Finders keepers, she told me.

Output: I (myself), My wife

Input: Consider Input: Sentence1: Tom was in the local park one afternoon. Sentence2: He saw a rather disobedient dog in the distance. Sentence3: The dog's owner through a frisbee in Tom's direction. Sentence4: Unfortunately, the dog decided to pounce on Tom instead. Sentence5: The dog's owner didn't even apologize.
Output: Owner, Dog, Tom