Sahih Muslim 774
Sahih Muslim · Book 6: The Book of Prayer - Travellers · Encouragement to pray at night even if it is little
'Abdullah (b. Mas'ud) reported that a mention was made of a man who slept the whole night till morning. He (the Holy Prophet) remarked:
حَدَّثَنَا عُثْمَانُ بْنُ أَبِي شَيْبَةَ ، وَإِسْحَاقُ ، قَالَ عُثْمَانُ حَدَّثَنَا جَرِيرٌ ، عَنْ مَنْصُورٍ ، عَنْ أَبِي وَائِلٍ ، عَنْ عَبْدِ اللَّهِ ، قَالَ ذُكِرَ عِنْدَ رَسُولِ اللَّهِ صلى الله عليه وسلم رَجُلٌ نَامَ لَيْلَةً حَتَّى أَصْبَحَ قَالَ " ذَاكَ رَجُلٌ بَالَ الشَّيْطَانُ فِي أُذُنَيْهِ " . أَوْ قَالَ " فِي أُذُنِهِ " .
That is a man in whose ears (or in whose ear) the devil urinated.