He witnessed me rubbing off the semen from the clothe of the Messenger of Allah (ﷺ).

Abu Dawud said: Al-A'mash narrated it as narrated by al-Hakam.
Sunan Abi Dawud Book 1, Hadith 371
← Previous Hadith The Messenger of Allah (ﷺ) would pray at night while I lay by his side during my menstrual period. A sheet of cloth would be partly on me and partly on him.

Sunan Abi Dawud Book 1, Hadith 370 Next Hadith → I used to rub off the semen from the clothe of the Messenger of Allah (ﷺ). He would would pray in it.

Abu Dawud said: Mughirah, Abu Ma'shar, and Wasil also narrated it to the same effect.

Sunan Abi Dawud Book 1, Hadith 372