The phrase kto sie zesral is Polish slang built around a very crude verb for defecating, so the question is intentionally vulgar rather than polite. Clips of short spoken accusations like this circulate on soundboards and in meme edits because they work without context and can be reused for any embarrassing scene. There is no documented original source for this recording, and it is shared mainly for its prank value among Polish speaking users who recognise the insult instantly and use it to tease friends in chats and videos.