I want to train you to be a better partner. That means actively listening to what your girlfriend wants and needs, and meeting that. If you cum before She does, it's premature and certain to leave Her unsatisfied. Grab a condom and put it on your dick. This will desensitize your pleasure to help you last longer. I'm going to instruct you to jerk off with a condom on your cock, demonstrating how I want you to stroke for Me using a realistic dildo, teasing and edging you until satisfied, before counting you down to orgasm. A good sexual partner ensures that She always cums first, and maybe second and third, too.