Agarez himself had human blood and after he grew up as an adult, he was influenced by human being's culture deeply, therefore he disliked his own identity as a Devil. That was why his favorite concubine was a human being. But even inside the Moon Devil clan, only one third of the members were trusted ones and those who knew this secret were very few. He had to be careful! He wanted to overthrow the God of Devils but he was scared to do so, especially because he was so close to him and he knew how scary he could be.
For example, last time when the God of Devils and Star Devil God set a trap for Long Haochen, Agarez did not even know the details. He only knew about the trap when he went back to Xincheng with the God of Devils, but he did not get any chances to send the message out because they were always together and that caused Long Haochen's death.
