Uti-puti has long been used in Russian as affectionate baby talk, the kind of soft nonsense words adults say to infants and small animals to show fondness. Online, the phrase became a handy shorthand for anything overwhelmingly cute, and short clips of it spread on TikTok and other short video platforms as a reaction sound. Creators reuse it for pets, babies, anime style edits and wholesome moments because the meaning is clear even without translation, and its gentle tone contrasts humorously with how seriously people dote on their subject.