Episode 21: Enhou finally died as herself and in the eyes of her subordinates, as a true hero.
Also, the bar scene, with the shared camaraderie between the Makai Knights and SG-1's troopers, and Enhou's children with her boyfriend happily greeting her. It's really heartbreaking, because it shows what could have been had Enhou not been turned into a Madou Horror.
Episode 23: Right after Ryuga had defeated Sonshi and managed to restore the armor of GARO to its golden brilliance, he was forced to kill his own mother due to And Then Hakana Was A Horror, which was caused by her being forced to give birth to multiple Madou Horror Plants. What really twists the knife is the fact that she didn't even get to see its golden glow due to having let herself be blinded to restore Ryuga's eyesight.