The phrase combines Mexican slang 'no mames', used to express disbelief, with 'te la creíste', meaning you actually believed it, making it a natural taunt after a successful joke. It spread through Spanish-language TikTok videos and short-form pranks, where creators used the short clip to punctuate the moment a trick was revealed. Its appeal lies in its brevity and attitude, which translate even for viewers who only partly understand Spanish. Today it remains a staple reaction sound for pranks, fake news jokes and playful teasing among friends online.