Targum sobre Rut 3:10

Said he: "Blessed be you before the Lord, my daughter. The last good deed which you have done is better than the first. The first was that you became a proselyte, and the last, that you made yourself like a woman who waits for a small brother-in-law until he grows up, refraining from following young men, whether poor or wealthy, in order to carry on immoral relations with them.