Abu Dawud
Hot Baths
Book Number: 026 / Hadith Number: 4007
Narated By Abu Sa'id al-Khudri : The Prophet (pbuh) said: A man should not look at the private parts of another man, and a woman should not look at the private parts of another woman. A man should not lie with another man without wearing lower garment under one cover; and a woman should not be lie with another woman without wearing lower garment under one cover.