His greatest pleasure of them all was the mental torture he was putting himself through every time he was doing it. Sex was only physical before that, while now his mind was having sex as well. It's the best thing that had happened to him ever. Humankind had fulfilled his dreams and desires by dieing.
All that remained of humanity was Pedro and two babies. Not a pretty picture. For Pedro, chance had finally died and, as any man who sees himself cornered by certainty, he thought of the most important thing he could do for himself and for the babies. Feeding.