The phrase blends two pieces of internet slang that collided in the early 2020s. Sus, shortened to sussy, became everyday gaming slang for suspicious during the huge popularity of Among Us, while baka is a long-used Japanese insult meaning fool, familiar to anime fans. Put together, sussy baka became a mock-serious accusation people posted, imitated and remixed across short-form video and meme pages. The stretched bakaaaa version exaggerates that delivery even further, turning a quick insult into a drawn-out punchline that still works as a reaction sound.