The exact song behind this upload is not identified in its listing, so the clip is best understood as a short user-uploaded IU excerpt rather than a named single. IU, whose real name is Lee Ji-eun, is a known South Korean singer and songwriter, and short clips like this circulate among fans who make edits, tributes and reaction videos. Because the excerpt is only fifteen seconds long, it fits the pacing of short-form video, where a familiar voice can set the mood instantly without needing the full track. That brevity is part of why it keeps being reused.