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.

Sentence1: Tim liked to post political memes online. Sentence2: One day a friend responded negatively to one. Sentence3: Tim felt insulted and started to argue. Sentence4: They both got offended at each other. Sentence5: Tim and the friend stopped talking afterward.
Tim, Friend