Amelia had deliberately brought Adam to this state. She needed to ensure he had no powers left to continue fighting and that his energy was depleted as well.
This was her best chance to fulfill her part of the deal, since she had lied to Adam during their first meeting.
It was impossible to teach someone the Soul Stance with any guarantee of success. Amelia could try to use every resource at her disposal, but if Adam wasn't capable of doing it on his own, there was nothing she could do to change that.
Basically, Amelia had to help Adam harness this power much sooner than it would have happened otherwise.
Draining Adam of his energy was her best chance to force him to awaken the Soul Stance, at least a small part of it.
Step.
Amelia stepped forward and attacked. She was ready to go all the way and inflict a serious wound on Adam if necessary.
Soon, she saw what she had been waiting for so long.
"This is…!" Her eyes widened as Adam used the only thing he had, his aura.
