After Naraku received Kikyo's tenderness, he never wanted to let go. When he learned that Kikyo fell in love with InuYasha, he used a trick to kill InuYasha and obtained a half-demon body. I thought I could get her this way, but I didn't expect she died. She is dead..., Since she is dead, this world will not exist. So Naraku embarked on the path of destroying the world.