"The Messenger of Allah would become sexually impure and then sleep without water until he got up later on and taken a bath." (Using translation from Ibn Mājah 581)
كَانَ رَسُولُ اللهِ ﷺ يُجْنِبُ ثُمَّ يَنَامُ وَلَا يَمَسُّ مَاءً حَتَّى يَقُومَ بَعْدَ ذَلِكَ فَيَغْتَسِلَ