وَعَنْ أَبِي هُرَيْرَةَ رضى الله عنه
قَالَ: قَالَ رَسُولُ اَللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ -«إِذَا جَلَسَ بَيْنَ شُعَبِهَا اَلْأَرْبَعِ، ثُمَّ جَهَدَهَا، فَقَدْ وَجَبَ اَلْغُسْلُ»
The Messenger of Allah (sallallahu alayhi wa sallam) said that, “If one of you sits between her legs (of a woman) and penetrates her, Ghusl (bath) is obligatory.”.