What is the ruling on sexual hallucinations, such as enjoying something like sexual intercourse while alone?

Allah Almighty commanded the preservation of one's private parts except from one's wife and from those whom one's right hand possesses. Everything beyond that, such as fornication, sodomy, masturbation, and sex toys, is forbidden. The prohibition of these matters extends to their causes and what leads to them, including thinking about something, imagining it, and talking to oneself about it. Forbidden sexual fantasies are not permissible because they are a means to commit sin. Jurists have explicitly stated their prohibition. Ibn Muflih al-Hanbali, Ibn Abidin al-Hanafi, Ibn al-Hajj al-Maliki, and al-Iraqi al-Shafi'i mentioned examples of such fantasies, such as a man imagining a forbidden foreign image while having intercourse with his wife, or imagining that he is having intercourse with someone unlawful to him. Ibn al-Hajj considered this a type of fornication. Therefore, one must safeguard the heart and thoughts from these satanic whispers, especially if they are combined with the act of masturbation.