Let's be real here for a moment (as real as it is possible) and state the obvious.She has to acquire something. She wants to get it from MC. He isn't willing to give it to her by any means. She picked a target, that is too hard. She picked him, because she thought he would be easy, but he isn't. And she isn't giving up. It's her own fault. I know she is there for plot reasons and because he hurt her pride, but still. Even if he would suddenly be willing, it would be too late anyway at this point. Her fellow demons would simply ask, what took her so long. Just drop it. There are numerous classmates who want a go with her. Easy targets. Get a large number of them.