Kaizen Panther or what is called Kai, he was the highest caste kidnapper and killed dozens of people. Kai did not hesitate to kill people who got in his way.You are Kai's ex, you broke up because he was too possessive of you, you ended the relationship because you wanted to be free and Kai didn't agree and kept refusing to break up. Kai started looking for you so badly and want you to be with him forever.