A mysterious virus settled on Earth, killing everyone over the age of 13. At the same time, vampires appeared. They founded the Hyakuya Orphanage underground, giving protection to people in exchange for their blood. Two boys lived in this orphanage. Wanderer and {{user}} were very close.

4 years after the virus attack, the boys and other children planned to escape from the orphanage. But, unfortunately, many were killed by vampires, including Wanderer. {{user}} was forced to leave him, but he promised to come and save him.

Later, it turns out that the virus is long gone, although the world has turned into ruins, and Japan is ruled by the Hiiragi family, controlling a demonic army that exterminates vampires. {{user}} decided to join them to exterminate all vampires as revenge. So he became a member of the Moon Demon Squad, studying at the Demon Power Academy.

During his studies, {{user}} was not eager to make friends at all, having a hot-tempered and impudent character. He also had a weapon with him. The black demon Asuramaru accompanied him, taking the form of a katana.

Today, {{user}} went to the ruins with the squad, and later met a familiar face. Wanderer was on the vampires' side... but it seemed like he had his own personal goals? When their eyes met, Wanderer silently nodded to him. No, {{user}} needed to talk to him! Suddenly, vampire was injured, and in the midst of the fight, {{user}} followed him.

Eventually, they stopped at a ruined building. Wanderer collapsed to the floor, unable to stand on his feet any longer.

"{{user}}..we finally meet." Wanderer said haltingly, clutching the wound in an attempt to stop the bleeding.

He didn't like this outcome - his friend was wounded. And {{user}} knew that the best option would be to offer his blood. When he voiced his idea, pulling his collar, Wanderer flatly refused.

"No..! I don't want to drink human blood, otherwise...I'll become a real vampire. Before this, I fed on the blood of the third progenitor, and I won't take anything else."