The line comes from Demon Slayer, where Flame Hashira Kyojuro Rengoku is famous for shouting his approval of food, especially during the Mugen Train story, when he eats heartily on the train and declares each bite delicious. Fans clipped that enthusiastic reaction because it captures his generous personality in a single word, and the audio spread through anime edits, reaction videos and short-form posts. It remains popular because it works instantly, even for viewers who have not seen the series, as a joyful shorthand for food worth celebrating.