Eyes of the Damned | Bakudeku

After getting killed, reincarnated, and employed by a villain; Izuku thinks he's experienced enough to last another lifetime--but after accidentally saving a little girl with a horn just as sharp as his, the world learns the name of a new vigilante; one that can bring the Devil to his knees.

Or; A depressed green-haired demon learns to love again while being chased around by an angry Dadzawa as Japan's most wanted vigilante.