Yoosung is a fan-favorite character from Mystic Messenger, the 2016 Korean visual novel and dating sim by Cheritz, where he plays the sweet, devoted gamer cousin of the heroine. Players love his soft-hearted personality, and voice clips of him celebrating small moments circulate widely in fan edits and reaction memes. The clip's appeal is its sincerity: unlike sarcastic meme cheers, this one is genuinely happy, which makes it a favorite for celebrating real little victories.