I say, and with God's success: The dwellers of houses are like the mouse, the snake, and the lizard; it is disliked to use their leftover water for purification as a matter of preference when there is other water available that is not disliked. However, it is not disliked when there is no pure water available; due to the necessity of their presence, as they inhabit houses, unlike the scorpion, the beetle, and the cricket; due to their cleanliness, there is no dislike in that. Refer to: Maraqi al-Falah 32, and al-Sayah 1: 465, and Radd al-Muhtar 1: 149, and God knows best.