Zofis

Zofis is a heartless, evil mamodo who desires to become king of the Mamodo World and rule with an iron fist.

To this end, he is willing to manipulate the hearts and minds of others through their desires, sadness, or fears, including his human partner, in order to gain the power necessary to crush all who stand in his way.

However, it is also seen that he takes a certain sadistic pleasure in the misery of others, as shown from how he laughed at Sherry's pain and stated that he always smiled at the destruction of a human's heart. He is also seen as somewhat of a genius and master tactician, as he was able to effectively lead the army of Ancient Mamodo that he assembled, as well as create the mysterious Stone of Moonlight to enhance his heart-controlling power.
(Source: Wikia)