Himeno and Hayate's first battle against a demon larva monster.
From the second-last episode, Natsue, Kaoru and Mayune trying to save Mawata from the Tree. We see them pulling on the vines over and over again. Even when they get physically attacked by lightning, and they haven't made any progress with the vines, they still don't give up. And when you consider Mayune and Kaoru have been comic relief characters up to that point, it makes it even more awesome.
Followed by Himeno's You Are Not Alone words to Mawata, which finishes the job magnificently — and sets the mood for Himeno redeeming Takako aka Fenrir also with kindness and understanding in the next episode.