This is the same guy who wants big boobs and knows he's a gigantic pervert. He does not want her to "stoop down to his level." That's a partner as in someone to be with but no love. I understand where Maruyama is coming from in where he thinks she deserves someone to be in love with and not just be together with. There are couples who don't love each other. There is no denying the fact that Maruyama likes her, cares for her, but does not love her yet
Loving someone makes you want to be a better person and change yourself. Maruyama doesn't realize it but he IS changing to become a better person. He is doing things he would never before just for her.
Believe it or not but I've seen it too many guys IRL that don't want to date a woman who they respect and like. My father has talked about this with me a lot where he has friends who passed on a girl they respected, liked, and thought she was a sweet girl but never wanted to date her. It drives me NUTS.