Rental Magica from Solomon

Due to his father's disappearance, Itsuki Iba has to take over the family business: a magician dispatch service. Their family basically employs countless magicians and other supernatural beings in order to send them out to help those who need magical assistance. As a leader, Itsuki now has to be tough, commanding, and reliable, but there's one problem, he's a coward. Also, in order to run a successful business, he has to connect with his employees, which is more difficult than it seems due to his personality. But not only does he have to deal with his own employees, he also has to deal with those who threaten the family business.
(Source: MU)