His cock quickly hardens under her touch and he peers down to watch her licking and jerking his cock. Her juices, coating his cock, were soon licked away by her tongue. He found that itself to be arousing, watching her lick her own juices off of him. He had no desire to taste his own cum but found it erotic that she seemed to enjoy her own taste. He was also aroused just watching her with his cock in hand - desires of lust and the thought of how wrong it was, for a mother to be sexually involved with her son, flooding his mind.