The Queen Attacks
It was not the first time that Layla had a tussle with Erin. She was aware of who the person in the armour was. Because not too long ago, Layla and a group of the Red vampires had gone out hoping to stop the Dhampirs' advance.
The truth was Layla was hoping that she could persuade them to leave and turn around. After all, she had a special link with Erin. However, it failed, but in the end, a fight broke out, and she even needed the power of the Celestial Sword.
It only took a couple of clashes against her old for Layla to confirm a few things. One, the amount of Qi they both had at the time was relatively even, but the power of the Dhampir, among other things such as the armour and weapons, made it so that Erin's strikes, speed and attack power were superior.
Then on top of that, there was the swordsmanship itself. Despite Layla trying to become a better swordsman, honing her skill with practice partners and more, she was no match against Erin.