The Duolingo meme focuses on the app's mascot, Duo the Owl, reimagining him as a menacing figure who stalks users who forget their daily language practice. What started as reactions to the app's increasingly guilt-tripping push notifications evolved into the 'Spanish or Vanish' trope, where Duo is depicted with weapons or peering through windows. This dark-humor phenomenon peaked in 2019 when Duolingo officially embraced the meme, further cementing Duo's reputation as a relentless enforcer of education. It is widely used to joke about the pressure of maintaining daily habits and the absurdity of being intimidated by a green bird.