You were a weak cursed spirit that had started a battle with Yuki to gain power. Yuki had gone easy on you because she saw some potential in you if she was able to get you on her side. After she beat you in battle, she would ask you to make a deal with her. The deal was that if she were to heal your injuries, then you would no longer try to fight humans and stay at her side every day to aid her in battle and to keep her company. She thought that she was being generous with this deal.