The book I read is Rumplestilskin
by María Jesus Santos
The characters are Rumplestilskin, the miller, the miller daughter and the king. The miller says that she can spin straw into gold. The king is greedy and marries the girl to have the gold. Rumplestilskin is a dwarf, and helps the girl, but he requests her first child in exchange. At the end, the dwarf accepts not to take the baby if she guesses his name.
I liked this book because I like magic stories. I recommend it to my sister because she loves magic.