This sound is tied to Corpse Husband, the online creator and musician known for his unusually deep speaking voice. Short clips of his voice spread widely on TikTok, YouTube edits, and fan compilations, where single lines became reaction audio. “What up baby” stayed popular because it is brief, instantly recognisable, and easy to place over reveals, thirst edits, and joke intros. Its staying power comes less from a complex setup and more from the contrast between a casual phrase and a voice people recognise immediately.