As soon as Stella saw the state Rein was in, her mind immediately got clouded in anger. She was obviously angry at the dragon to hurt Rein so badly but she was even more angry at herself for not paying enough attention to the battle.
Rein got hurt so badly because he was trying to protect her. Even when half of his body had disappeared, he was still not in any danger. But for the time being he would not be able to attack anymore as that wound would take a lot of time to heal even for someone like Rein.
So, Stella channeled all her rage into strengthening her willpower and did something very dangerous that she had never done before. She started to utilise the power of the spirit of magic exceeding her limits.
