Is it Islamically permissible to masturbate over the phone and for the fiancé to request photos of sensitive parts of his fiancée before consummating the marriage, and is it possible to repent from that and convince the fiancé of its impermissibility?

Once the marriage contract is concluded with its conditions, the woman becomes permissible for her husband, and they are allowed to enjoy each other within the bounds of Islamic law, while observing customs by refraining from intercourse before the wedding. There is no harm in the spouses talking about private matters that lead to the emission of semen due to speech, provided there is no masturbation by hand, and ensuring that no one else overhears. It is advisable to avoid speech that incites lust, which could lead to what is forbidden. Masturbation is forbidden and not permissible under any circumstances, just as sending pictures of private parts is not permissible; because pictures are a matter of scholarly disagreement, and sending them exposes them to the risk of falling into the hands of someone other than the husband, which causes great corruption. The husband must refrain from asking for that, and the wife must not obey him in this matter.