Peter Abel Nightroad is the main character in 'Trinity Blood'. He had made a promise not to kill anyone to pay off his past sins even if it ment for him to die. Abel is a priest and a Crusnik Vampire, meaning he drinks Vampire blood and only Vampire blood. He protects humans. However, he is also part of "Ax", a special operations group controlled by the Cardinal Catherina. His encounter with a young girl called Esther will determine the struggle and survival between the human race and the vampires.
Abel is an AX agent for the with extraordinary powers granted by the Crusnik nanomachines. The nano-technology was found on Mars while humanity attempted to colonize Earth. During the process, the Bacillus was also found. The Bacillus transformed the colonists into vampires known as Methuselah while the Crusnik turned four select test tube babies into something higher in the food chain. Abel was one of them but the exact means of circumstances are still unknown. Anyhow, with these new abilities, he was forced to pick a side during a massive war between the Methuselah and the humans called "Terrans" by the vampires. Abel, along with his brother Cain and his sister Seth, joined the Methuselah. During this time, Abel slaughters seven million humans while his sister Lilith fought the front allying with the humans who were supported by the . While he continued to fight, his insane brother Cain killed Lilith forcing Abel in a state of sorrow but not before throwing his own brother out of the space ship, to what he thought was his doom. Weeping at Lilith's grave for 900 years, Abel eventually pledged his allegiance to the and the Ministry of Holy Affairs.
In the year 3055 A.D, he joined the AX, short for Arcanum Cella Ex Dono Dei(Latin for Papal State Affairs Special Operations Section). They are elite nuns and priests with powers granted by lost technologies. They serve under Cardinal Caterina Sforza and their missions require them to investigate vampires. Though obviously powerful, Abel is a pacifist and masks himself in clumsy nature only summoning his Crusnik powers when absolutely necessary.
In his travels, he meets a nun by the name of Esther Blanchett and is hesitant to use his Crusnik form for the fear of her seeing him in it. Once he does however, depending on the adaptation, he becomes engulfed in sorrow and distraught yet she still joins AX nevertheless. He becomes like a fatherly figure to her but Esther has much more romantic feelings for Abel. It is unknown whether or not he shares the same feelings for Esther but when he thought she had been murdered, he loses control and appeared to enjoy killing the Methuselah Radu. In the aftermath of this, Esther aids in Abel's return to his human form. Not much later, he learns of Cain's return and pledges to kill his brother once and for all. In their first meeting, Cain beats Abel because of his superior Crusnik fusion and also because he was distracted by Esther. He entered a near death state with his brother attempting to merge with him in order to recover the codes for the missile control panel Abel had destroyed. Father Tres interferes, even though he his no match for the Crusnik Abel is revived using Lilith's nanomachines granting him a 100% Crusnik form in which he fights his brother to a draw. Afterward, Abel along with Father Fortuna, go off in search of Cain to battle until one of them finally dies.
Abel is a great marksman fighting with pistols load with silver bullets. In order to activate his Crusnik form, he issues a verbal or mental command but it isn't necessary. The verbal command, depending on the method and wording, will unlock certain stages of his Crusnik powers but depending on the adaptation the commands differ slightly. When at 40% activation, his teeth become fangs, lips become a dark blue color and his eyes turn red. In this state, he can summon a scythe from crystallizing his blood. At 80%, Abel will grow black wings, nails will elongate while generating collosal amounts of electricity from his body to use as blasts or shields. Only in the anime is he able to achieve 100% but he becomes something similar to a demon with dark skin, bat like wings and blue markings covering his body. In this state, he can generate even more electricity then in his 80% form and a second blade on the opposite end of the scythe will appear.