Scenario (made up)
Keep in mind my wife can't get pregnant and in this scene she's with one of my best friends, Carl. She and I just wanted to get a clear
crème-pie shot for content. I'm behind the camera with a monitor off to my right. We all the shot we want to achieve. As Carl and my wife are at it, she tells him, "Don't release too deep. It's too hard to push out". Carl obliged and came in he with his cock only 2/3 the way in. He pulls out and my wife looks to the monitor to see how the shot went.
Remember there's no love affection here. Carl is just someone we trust. My wife sees him as someone who can help us with this "lifestyle". She sees his cock as something more comfortable and attractive than a dildo. And that Carl gets some enjoyment out of it as well.