The exact original source of this clip is not clearly documented, but it circulates as a French TikTok trend built around a monster greeting and the word coucou. Short-form creators reuse it because the friendly monster voice is instantly recognisable in a feed, even without context, and it pairs easily with costumes, pets and surprise reveals. Its short length also suits quick edits, duets and reaction formats, which has helped it keep appearing in new videos long after its first wave of posts.