Unfortunately there's no way to reduce it. It can be embarassing when it soaks through your jeans. Cotton underwear like briefs could help reduce this.
Is there any way to reduce the ammount of pre-***? This seem like an extreme amount, it has soaked through my jeans before.
With slight contact it's more likely that what's in your pants is pre-ejaculate (sometimes called pre-***). If you're not having an orgasm when this happens that's almost definitely what it is. It's clearer than semen and "stickier." It's purpose is to lubricate your urethra (the tube in your penis that urine and semen pass through) and also to adjust the pH to make it more "sperm friendly." Some guys produce more than others and unlike semen, masturbation won't reduce the volume.
It's normal for one testicle to be larger than the other (usually the left) and the "tube", which is actually your vas deferens, might also be larger on one side. Both perfectly normal. A lump that goes away is nothing to worry about, most likely it's a temporary build up of sperm in your epididymis.