A Catholic priest who seems to be nothing more than a clumsy, absent-minded fool on the surface. In truth, he is a Crusnik, a vampire of extreme, extraordinary power, and is an ancient being, hundreds of years old. He is a vampire that feeds on the blood of vampires. But despite his strength, he adheres to a principle of pacifism and often refuses to outright kill his opponents, also he has sworn to never kill a human again and adheres to that promise regardless of how hard it gets for him to do so. Abel is shown in flashbacks to have a hatred for humanity, but at some point that changes into his current pacifistic and peaceful outlook on life. He acknowledges having greatly sinned at some point in his life, though it is unclear as to what sin he committed, and much of his current personality is based on retribution for his sins. Abel has at one point referred to his Crusnik form as "a mark of his sins", though it is unknown what he meant by that. He has feelings towards Esther Blanchett, though they are more related to her similarities with a woman from his past. In his human form he fights with a gun that shoots silver bullets. As a Crusnik, is able to transform into various forms based on the amount of nanomachines in his body that he activates. In his higher forms he wields a huge scythe materialized from his own blood. In The Star Of Sorrow II, it is revealed that pre-Armageddon, Nightroad was Commander in the UN Air and Space Force involved in the "Red Mars" project. [...]

The following information may contain spoilers for those who wish to read the manga/novel:

(Source: Wikipedia)