Excuse my language but what the hell is "ombre"? I'd assume it's some shade of brown or something but it I don't think I've heard it before.
Gradient hair. Specifically, progressing from dark shades at the roots to light at the end.
That said, Asashio's hair here seems to be black (or dark brown) all over. The washed-out effect and the other colors appear to just be a lighting effect.
