Eclipse

A powerful and ancient high ranking demon whose occupation consists of serving those of the Raenef name. It is revealed that his services are highly sought after by many demon lords. He is charged with finding the newest Lord Raenef Raenef V and educating him. Though the newest demon lord never ceases to annoy and exasperate him he comes to care very deeply for the innocent boy. He and Raenef IV are implied to have had a relatively close relationship which becomes a point of conflict later in the series. Source: Wikipedia