The clip comes from Himouto! Umaru-chan, the manga by Sankaku Head adapted into an anime in 2015, following Umaru Doma, a perfect student who becomes a lazy chibi gamer at home with her brother Taihei. Her repeated Onii-chan, onii-chan calls became a shorthand for the spoiled imouto trope online, shared alongside other catchphrases like Tuturu in anime soundboards and edits. Fans still use it on TikTok and Discord to joke about clingy siblings, begging for food, or acting cute to avoid chores and homework.