I sometimes doubt, before or after urinating, or even during sexual arousal, a liquid comes out of the urine,…

Answer

The fluid that sometimes comes out of the penis as a result of sexual arousal, called ‘madhī’, is pure. And the fluid that sometimes comes out after the ejaculation of semen, called ‘wadhī’, is also pure, and does not require ghusl. As for fluid that sometimes comes out after urinating and which is called ‘wadī’, if it has not come into contact with urine, it is pure. Furthermore, in the event that a person performs istibrāʾ after urinating and then fluid comes out and he doubts whether it is urine or one of these three fluids, it is pure. The passing of these liquids are pure and do not invalidate wuḍūʾ either.