Is it permissible to pray two rak'ahs for repentance and seeking forgiveness after being negligent in performing a Sunnah, or abandoning it, or lacking devotion in prayer? And is it true that Satan cannot bear for a servant to pray two rak'ahs voluntarily for Allah?

There is no objection to praying two rak'ahs of repentance after falling short or committing a disliked act, following the example of the Prophet (peace be upon him) and the practice of the predecessors. Among what has been narrated in this regard is the hadith of Abu Bakr Al-Siddiq (may Allah be pleased with him) from the Prophet (peace be upon him): "There is no man who commits a sin, then gets up and purifies himself, then prays, then seeks Allah's forgiveness, but Allah will forgive him." Examples of this include what Al-Muzani (may Allah have mercy on him) did by repeating his prayer twenty-five times if he missed congregational prayer, and what Ibn Wahb (may Allah have mercy on him) did by giving a dirham in charity whenever he backbit someone.