Ah... yes, I think Cain might well be able to help you there. The Commissariat leads the soldiers of the Imperium against many things, from the xeno, to the heretic, to the daemon.
But I'll humor you and ask, what are Akuma specifically? [ He lays a hand on his own sword, as if contemplating drawing it, but his body language isn't of that of someone about to take a swing. Rather, he appears to be contemplating if he should draw it as if to demonstrate a point, instead. ]