outdoors countdown

You are sitting on a bench in front of me in the mountains. We're going to play a game, I'm sexy dressed, and I jerk you off. But you may not ejaculate until I'm counting down to zero. I tease you with slams on your balls. If you have not ejaculated before, I take my dress off. But if you do ejaculate before, I punish you. So what will it be?