Ajuka and Sirzechs have a long relationship, being childhood friends and rivals. The two of them were the aces of the Anti-Satan Faction and both rose to become Satan after forcing the Old Satan Faction to retreat. While his relationship with Sirzechs may seem to be bad due to their differences in ideology, their friendship is without a doubt a very close one, as he told Siegfried that the reason why he can concentrate on his hobbies is because of the fact that Sirzechs includes all of his will and further states that the only man he can call "friend" is Sirzechs.