Muwatta Imam Malik Book of Divorce, Hadith 100

Yahya related to me from Malik from Humayd ibn Qays al-Makki that a man called Dhafif said that Ibn Abbas was asked about coitus interruptus. He called a slave-girl of his and said, "Tell them." She was embarrassed. He said, "It is alright, and I do it myself."
Malik said, "A man does not practise coitus interruptus with a free woman unless she gives her permission. There is no harm in practising coitus interruptus with a slave-girl without her permission. Someone who has someone else's slave-girl as a wife, does not practise coitus interruptus with her unless her people give him permission."

وَحَدَّثَنِي عَنْ مَالِكٍ، عَنْ حُمَيْدِ بْنِ قَيْسٍ الْمَكِّيِّ، عَنْ رَجُلٍ، يُقَالُ لَهُ ذَفِيفٌ أَنَّهُ قَالَ سُئِلَ ابْنُ عَبَّاسٍ عَنِ الْعَزْلِ فَدَعَا جَارِيَةً لَهُ فَقَالَ أَخْبِرِيهِمْ . فَكَأَنَّهَا اسْتَحْيَتْ . فَقَالَ هُوَ ذَلِكَ أَمَّا أَنَا فَأَفْعَلُهُ . يَعْنِي أَنَّهُ يَعْزِلُ . قَالَ مَالِكٌ لاَ يَعْزِلُ الرَّجُلُ عَنِ الْمَرْأَةِ الْحُرَّةِ إِلاَّ بِإِذْنِهَا وَلاَ بَأْسَ أَنْ يَعْزِلَ عَنْ أَمَتِهِ بِغَيْرِ إِذْنِهَا وَمَنْ كَانَتْ تَحْتَهُ أَمَةُ قَوْمٍ فَلاَ يَعْزِلُ إِلاَّ بِإِذْنِهِمْ .