Is a person sinful if they desire someone in their imagination and imagine having sex with them, knowing that this desire is overwhelming and beyond their control?

Men are not permitted to gaze with lust, rather they must lower their gaze, as it is a cause of temptation and corruption of the heart. As for sexual fantasies, they are not permissible if deliberately sought out. If they occur unintentionally, there is no blame, but they must be resisted, because neglecting intrusive thoughts is the root of corruption. There is no harm for a woman to offer herself in marriage to a righteous man, provided it adheres to the prescribed Islamic guidelines.