His court appearance came after he turned himself over to the police at the weekend. Mr Sibiya claimed the timing was deliberate. Overcome with remorse after the attack, he said he been in torment for a period of four years.
Speaking through an interpreter, Mr Sibiya calmly described how he attacked the women with a bushknife and a spear in their station-wagon at Nine Mile beach on the Maputaland coast.
Their naked and wounded bodies were washed up, just hours later, near the Mozambique border.
He had robbed the women but four months after the attack he said he felt so guilty he burnt everything he had stolen along with his weapons and clothes. After that he had felt closer to God and begged him to be patient until the victims families had forgotten their sorrow.
Mr Sibiya did not request legal representation at the hearing and said he would accept any punishment. He said he was just walking on the beach when he saw the women and "that was when everything began to happen". The magistrate ordered him to see the district surgeon and he was remanded in custody until 23 December.
Ms Over and Mrs Godwin, mother of a 23-month-old girl, had been friends for more than 11 years. Ms Over, from St Albans, Hertfordshire, had recently moved to South Africa to work as an advertising executive in Durban. Mrs Godwin, from Spratton, Northamptonshire, was to have been joined by her husband Tim and her daughter later on the trip.