Normally whenever i masturbate my semen comes out as a pretty normal consistency but ive noticed that after foreplay (making out for a long time, dry humping, etc.) my semen tends to come out very thin/watery. how do i stop this from happening?

More frequent ejaculation is a common cause of more watery sperm. I'm not sure that your sperm is abnormal as it's not always watery. Try less masturbation or consult a urologist if you still have concerns. A sperm analysis can be done to assure your sperm is normal.and that you don't have a low sperm count which is another cause of more watery sperm.

When indulging in foreplay what comes out is a thin sticky secretion designed to help lubricate by nature- also called-'pre-cum'. This i not the same as what comes out when you masturbate- which is the ejaculate or 'cum' and is much thicker. You cant stop pre-cum if sexually aroused. Both are normal.