You might have to be very cautious with this position since the penis is positioned in a very awkward position. Most men’s penis will stand straight up when erect and positioning it downward may be painful for the male.
For extra stimulation the female can rub her hands against his back.
Furthermore the female must keep her legs spread out while the male sits down on her thighs.
Again it is important that you watch what you do since this is not a position that most males can do.