Answered by Shaykh Faraz Rabbani
Would ghusl be required for the wetness/discharge a woman feels when aroused without a partner? Not masturbation, just arousal through dirty thoughts?
Walaikum assalam wa rahmatullah,
Such thoughts are haram. See attached answer(s).
Unless they lead to an orgasm, they do not require a ritual bath (ghusl), though the discharge itself is filthy and would require ablutions (wudu).
Are bad thoughts haram, or merely acting on them
Are bad thoughts counted against you by the recording angels