Kozuki Kuroi 黒井弧月
Kobushi's younger sister and the other Black Fist. She has a teleportation ability as well, but she can only teleport other people and things, not herself, just by touching them. She desires the title of "Black Fist" in the Kuroi family, and to do that she must steal something valuable enough to please their grandmother. As such, she joins the Professor for her own reasons.