Kaidan's powers come from a demon called the Bake-Neko, who gave her the choice to take either her place in the world or her mothers. Knowing this, her mother was cold to Kaidan her whole life intending to make her choice easy. Kaiden insted told the demon to spare her mother and take her place instead. The choice was a test and her selflessness allowed both her mother and her to live and Kaidan to inherit the power. Plutonian's Rampage
After Plutonian began killing off her teammates
Kaidan found she could summon them as well.