Answered by Shaykh Faraz Rabbani
Would it be permissible for my wife to pierce her nipples or navel for my pleasure?

Wa Alaykum Assalam wa Rahmatullah wa Barakatuhu,
In the Name of Allah, Most Merciful & Compassionate
The scholars limited the permissibility of piercing the body to the ears and nose (if customarily accepted, whether in one’s area or among upright Muslims). [Ibn Abidin, Radd al-Muhtar]
And Allah alone gives success.
Faraz Rabbani.
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