The feat can only be gained as approved by your DM/GM.

Your god/goddess has blessed you and your wings have become permanent and are always visible. If you're a fallen Aasimar, your Aasimar sub-race has not changed, but your wings become feathered or leathery (like a dragon or bat) in order to function for flight.  You now permanently gain the ability to fly with a fly speed of 60ft.