Wilson explains all

"Wilson, what are your talking about? Primitive native rituals? This is Heidi, not some native in a grass hut." Tim had finally come out of his daze and was sizing up the situation. He didn't look all that happy. Al, meanwhile, continued sitting in his chair, his dick hanging out and slick with the evidence of having fucked his lovely co-worker.

"Ah, Tim," Wilson kept stripping off his clothing, "you see it is a ancient need in the human species to assure that our off-spring are born as strong and healthy as possible. It is part of the rule for the survival of the species. Now, as you know, protein is essential for life. It is our basic building block...the foundation of our bodies...."

"Huh? What?" Tim was getting confused again. Heidi stood there, naked and still horny.

"Protein, Tim.... like all the meat you love to eat..."

"Meat! Ah, yeah, meat!" Wilson was speaking Tim's language now.

"Well, Tim," Wilson, finally naked, pointed to Heidi, Heidi's body craves protein to nourish her unborn child and the male seminal emissions contain vast quanities of protein."

"Emissions????" Tim was losing it again.

"Seminal fluid.... you know, cum! Heidi's body needs cum. We can do her and her child a great service now."

"Oh... yeah..." Tim looked at Heidi's round, naked body. His cock was already springing back for more action. "Serve Heidi...yeah..."

Wilson bent over, undid Heidi's work boots, and pulled them off with her overalls, panties, and socks. "Let's get Heidi into position!"