A Junub person should perform ablution before sleeping Sahih al-Bukhari 288
Arabic hadith text
حَدَّثَنَا يَحْيَى بْنُ بُكَيْرٍ، قَالَ حَدَّثَنَا اللَّيْثُ، عَنْ عُبَيْدِ اللَّهِ بْنِ أَبِي جَعْفَرٍ، عَنْ مُحَمَّدِ بْنِ عَبْدِ الرَّحْمَنِ، عَنْ عُرْوَةَ، عَنْ عَائِشَةَ، قَالَتْ كَانَ النَّبِيُّ صلى الله عليه وسلمإِذَا أَرَادَ أَنْ يَنَامَ وَهْوَ جُنُبٌ، غَسَلَ فَرْجَهُ، وَتَوَضَّأَ لِلصَّلاَةِ.
Translation
Narrated `Aisha
Whenever the Prophet (ﷺ) intended to sleep while he was Junub, he used to wash his private parts and perform ablution like that for the prayer.