@Jason Delong He has been training, training, training for 300 years in an enclosed place without any conctact aside for the 2 queens that only made him train until the last day (thet only slept with him the last night), mental growth is bound to your experiences and interactions with other people plus his body and brain didn't get old too, he growth in strength, magic, self esteem and common sense about his new power but you can ask him more specially when his first 10 years were in a g** forgoten town with not much education and the queens later only teached him magic and body enhancement...
"DO NOT PRAY! If you pray, your hands will close together. You will not be able to fight!" - Gattsu 