Main Vein
The large vein that travels the length of a cock. Instrumental in delivering blood from the central artery during erection.
Example:
My cock was so hard, my main vein was swollen with blood.
I saw my heart beat as the main vein of my cock pulsated with blood.
My cock was so hard, my main vein was swollen with blood.
I saw my heart beat as the main vein of my cock pulsated with blood.