¡Que no te falta!
She spilled water on his pants, and then she was gonna wash them and iron them. She says "Voy a planchar estos pantalones" and he says "Vaya, ¡Que no te falta!" and it seems like "if it's not too much trouble" certainly not don't miss a spot, no way he said that in this situation. Gracias.
2 Answers
I would translate it as meaning something like "I hope so" or "I hope you do it." Perhaps with the implication that she might not do it.
It was nothing like that, She was insisting and he didn't want to trouble her, he wanted to leave and she was insisting that he stay, and he is shy and can't speak well to woman so he can't help but stay and wait.