He takes care of the prodigal son.

Eiji, who comes from a wealthy family, spends the majority of his life as a student having fun with girls and enjoying the freedom that has been his own since leaving the family home. One day, his father, Eiichirou, discovers his disastrous results and forces him to return home, where he will have to undergo a formal upgrade in order to be able to take over the family business. Izumi, his personal servant, placed at his service by his father, will have the mission to help him in this task. But Eiji soon realized, that Izumi, under his politeness, doesn't seem to appreciate his new master very much, if at all... (Source: MU)