Koroche is a common everyday Russian word used to introduce a summary, similar to saying in short or basically in English. As a standalone soundboard clip it spread through Russian speaking meme spaces, chats and short video edits where a single word can set up an entire joke. Because the meaning is understood even from tone alone, it crossed into wider meme use as a reaction sound. It remains popular for edits that mock long introductions, overly detailed explanations and friends who never get straight to the point.