All over her face.

You can't hold it in much longer and you tell Sabrina to sit back. You jerk your cock a few times and feel your orgasm explode. You shoot stream after stream of cum onto Sabrina's beautiful face. Sabrina looks up at you as you paint her face with semen. The view is amazing, and you can't help but admire your work.

Once you're finished you tell Sabrina to get back up.

"You can go wash off in the bathroom. Then you can come back here and we will work on the project. However, when you come back, I don't want to hear a single word about what just happened unless I bring it up," you say, "I want to focus on getting this done, and you are going to obey me or the increasing amount of compromising videos you have been starring in will be all over the internet. In fact, I revealed myself to you because you should comprehend that I plan to use you until I tire of you, or feel you have done enough to deserve being released."

"But John, why would you do this?" Sabrina asks, sounding as if she's about to burst into tears.

"As I said, you can go wash off in the bathroom now. End of discussion," you say, completely ignoring her question.

Sabrina nods silently and gets up, cum still covering her face. She peeks out the door just to double check there is nobody left, then leaves. When she comes back, she's all cleaned up, her makeup pristine as usual. She sits down, avoiding eye contact, and the two of you get to work.

A couple hours later, the two of you have made substantial progress. Another night and you'll be finished with the presentation.