It is narrated about Tawoos, Saeed, Mujahid, and Ata’ (may Allah have mercy on them) that they strongly forbade intercourse with women in the anus (the place of excretion), and they said that this is disbelief.
Hadith Referenceسنن دارمي / من كتاب الطهارة / 1180
Hadith Takhrijیہ اسناد صحیح ہے۔ دیکھئے: [مصنف ابن أبى شيبه 74/1] ، [الدر المنثور 262/1]
Brief Explanation
(Explanation of Ahadith 1171 to 1180)
And this is also the position of the majority of scholars; no one has permitted this vile act, because in the clear texts of Islamic law there is severe prohibition of it. Therefore, intercourse in the anus is forbidden, which can even lead to disbelief.