Do unintentional sexual fantasies, which are not accompanied by indulgence or pleasure, and lead to the emission of fluid without lust, necessitate Ghusl, and are they considered whisperings (Waswas)?

So long as these thoughts come to mind without intention or indulgence, there is no sin in them. They are whisperings from Satan, and one must stay away from them and not indulge in them. If what comes out is madhiy (pre-seminal fluid), then it is impure and invalidates ablution (wudu'). However, if it is maniy (seminal fluid) and exits without desire, it does not necessitate ghusl (ritual bath) according to the majority of scholars. Ghusl is only obligatory when maniy exits with customary pleasure. Mere thinking or looking does not necessitate ghusl.