Lee Kyung-eun is a Korean picture-book author and illustrator who studied visual design and later trained in picture-book creation at Kkokdu Illustration Institute. She loves Harry Potter, comfortable sofas, imaginative worlds, and the freedom picture books offer to both children and adults. Her written-and-illustrated works include All Pigs, I Don’t Want to Get Up, and Knock, Knock, Knock. Lee’s work is characterized by playful visual humor, child-centered imagination, and an affectionate interest in the small emotional moments of everyday life. In Knock, Knock, Knock, she combines riddles, repetition, fantasy characters, and sibling affection to turn a search for a birthday gift into a warm adventure.