Hamatora THE NOVEL

In this world, there are people known as "Minimum Holders" who are capable of specific "small miracles." A government funded elite academy trains these Minimum Holders in order for them to reach their maximum potential and serve national interests. Once, a student, of great potential named Nice, dropped out. He started a private investigator team with an assistant named Hajime and seemed content solving cases for his clients (which often involve Minimum Holders). A top student of the academy, Murasaki, has been tasked with bringing Nice back. Murasaki bristles at the claim that Nice has a higher potential than he does, but he ends up involved in Nice's detective activities...

(Source: MangaHelpers)