As he saw the woman jump into the trees above, Grigori knew she needed his assistance. He charged toward the Grimm, screaming inarticulately so as to draw its attention. By the time it turned to face him, Grigori had managed to close most of the distance, and was ready to attack. Identifying his target as the Ursa Major, Grigori activated his gauntlets, using them simply to infuse his punches with the power of the dust loaded up.
He jumped into the air toward the beast, drawing his right arm back while extending the left toward the Ursa. As he moved through the air the Grimm began its rush to attack, just as Grigori planned. It jumped at him as he fell, opening its maw preparing to bite down. When his left fist was almost touching the snout of the monster in front of him, Grigori drew it back, instead launching his right fist at the beast's skull. The punch landed with a burst of flame and Grigori landed safely on the ground, Ursa crashing down next to him. Before it could stand up again, Grigori jumped into the air once more, punching down with his left fist at the Ursa. The punch landed and the Ursa began to freeze over from the impact point, still alive but incapacitated for a short time.
His assault on the Ursa Major finished for now, Grigori called out to the girl in green, "You're safe now. I'll let you kill it if you want to. Anyway, looks like we're partners in this shithole of a forest. Let's do what we need to do and get outta' here."