Due to a botched spell by Trixie, trying to find a faster way to transport herself to her next show, seven humans are transported to Equestria instead. A long series of events eventually lead to ponies and humans forming strong, emotional, physical relationships.
 
The Dragon Lands however, lack any humans.
 
So, after the humans are introduced to leaders and delegates of neighboring kingdoms, the benefits are painfully clear. Their soft skin, sensual touch… physical stamina… and a slew of other attributes have rapidly made the Equestrian Kingdom safer for the ponies and more dangerous to hostile forces.
 
After Ember’s attempts to bargain for the human that Fluttershy and Rarity have become romantically attached to fails, she demands to challenge them both in a show of strength for the family rights to their human.
 
Sadly, Ember wasn’t aware how much stronger having a human had made the ponies that she once viewed as soft and frail pushovers.