She agrees to his deal. She doesn't really have the option not to. So the imp teaches her how to spin the gold [he skips over this part as best he can. He sure doesn't know the whole story, here] and she spins the whole room to give to the King in the morning.

[This is where it starts deviating from what actually happened, big time, not that he knows that.]

She keeps spinning for the King, and then eventually she marries his son, the prince. They live happily for a while, until she has her first baby and the imp comes back to get his end of the deal.