The mangaka struck gold with this specific challenge. It's almost classic shounen. MC has a flash of inspiration from an outside source and is using this newfound inspiration to beat the "antagonist." Of course, this is all going to blow up in his face (or more specifically, on her back).
People are complaining about the trashiness of the manga, but…of course it's trashy. The entire manga is an obvious hentai premise. Just read it for the laughs and awkward boners. If you expected true literature, then you're the idiot. Granted, the manga is definitely trash. But I like reading trash sometimes.