I heard about a mother gaining supernatural strength to lift a car off her kid, but never have I seen a woman break a devil's contract with the power of shota. :v
P.S: While having her break a ritual that, seemingly, nobody else managed to escape before is pretty bad ass and a cool scene -- it's very short sighted writing to have her "fall to darkness", but then almost immediately get herself out. So did she fall, or not? What was the point? To expose Mie, and get the arc over with?
Because it, surely, wasn't in order to have an emotional moment, here..