The Angry Koala meme features a close-up photo of a koala bearing its teeth or looking uncharacteristically aggressive, shattering the image of these marsupials as sleepy, docile creatures. Originally circulating on platforms like Tumblr and Reddit in the early 2010s, the image became a popular reaction face to represent unexpected frustration or a 'don't talk to me' attitude. It is frequently used in 'Expectation vs. Reality' jokes or to describe someone who looks cute but has a short fuse. Its lasting popularity stems from the comical contrast between the animal's fluffy appearance and its ferocious facial expression.