Anal sex is is really unhealthy. On moral issues, Catholicism follows a principle known as Natural Law. There is an unnatural and disproportional disparity of power between a couple during anal sex. Throughout history it has been more about power than love.
Can a married couple have anal sex? Is it a sin to have anal sex? What is permissible? Having counseled for over twenty years, this question is fairly new among Christ-followers.
What is the Bible's view of anal sex generally? Is it alright to engage in it in marriage? Is there scriptural basis to reject anal sex? The Bible does not say anything about anal sex between and husband and wife in marriage. The same situation also exists regarding self-masturbation and oral sex in marriage.
Anal sex is becoming less of a taboo, but it can be a daunting idea and consent is essential. Once a taboo, anal sex is now seen as an enjoyable addition to many sexual relationships. So now your partner wants to give it a try.