What is the ruling on sexual fantasy for married and unmarried individuals?

What a person imagines or speaks to themselves about does not entail a ruling as long as it remains a mere thought or imagination that has not settled in the soul, based on the Prophet's (peace be upon him) saying: "Indeed, Allah has pardoned for my Ummah what they speak to themselves about, as long as they do not act upon it or speak of it."

A Muslim should avoid indulging in this type of thinking and busy themselves with what benefits them, and stay away from anything that leads to it, such as idleness and watching things that arouse instinct.

Indulging in imagining and intentionally thinking about what is unlawful is a means to the unlawful and is impermissible, because the means to something is like the thing itself.

Imagining someone unlawful during intimacy, for either spouse, is forbidden according to the majority of scholars.