等你长发及腰我就咔嚓剪掉
[dĕng nĭ zhăng fā jí yāo wŏ jiù kă cā jiăn diào]
Wait Until Your Long Hair Reaches Your Waist and I'll Chop It Off: An ironic expression where someone will perform an unexpected or contrary act after the other party finally achieves a goal or long-held desire.