Comes in three variants. Long single rope, Short single rope, and drizzle. To make the ropes of cum shoot out, make the particle for long and short single ropes last 0.5 seconds. Any longer and you will get little squirts here and there. Drizzle is self explanatory. Bind the particle to the penis model and rotate it to the correct angle of firing. Works best in lit room as the particle is not effected by light, that was the only way I could get it to work or the jizz would come out in different shades of black and grey. Ignore the particle names, they were actually edited existing particles from some game I ported to SFM.
same particle system as seen in my video: http://www.naughtymachinima.com/video/7 ... acking-off