Who was a writer on both "Roc Me Out" and "S&M", songs recorded by Barbadian recording artist Rihanna?
Roc Me Out:  It was written by Ester Dean, Robert Swire, Gareth McGrillen, Mikkel S. Eriksen and Tor Erik Hermansen. S&amp;M (song):  The American songwriter Ester Dean wrote "S&M" in collaboration with the producers Stargate and Sandy Vee.
Ester Dean