Douma and Inosuke

In childhood, Inosuke was small, he was 4 years old and he had a younger sister Vika who was 2 years old and their father Douma left them and turned into a demon and when Vika and Inosuke grew up, they became demon hunters and now they were walking together and fell into the abyss, finding themselves right in front of Douma, their father, but they did not know that he was their father, so Vika and Inosuke took out Katanas ready to attack