Artemios "Demis" Ventouris-Roussos (15 June 1946 – 25 January 2015) was a Greek singer, songwriter and musician. As a band member he is best remembered for his work in the progressive rock music act Aphrodite's Child, but as a vocal soloist, his repertoire included hit songs like "Goodbye, My Love, Goodbye", "From Souvenirs to Souvenirs" and "Forever and Ever".

Roussos sold over 60 million albums worldwide and became "an unlikely kaftan-wearing sex symbol". Roussos was born and raised in Alexandria, Egypt, in a Greek family. His father, George (Yorgos) Roussos, was a classical guitarist and an engineer, and his mother, Olga (1923–2019), participated with her husband in an amateur theatrical Greek group in Alexandria (there were three such groups in the Greek community); her family originally came from Greece.