This is vastly better than it has any right to be. For something with such an...honest...premise, it's great. The comedic timing is top notch, the main character is adorkable (lol), and the main girl is lovely and remarkably honest in her affections.
Though of course longevity is an issue. It has to either advance the relationship (and end the story, oops), add more girls (becoming one of those burdened harems with too many characters and too little depth to each), or add lower-case plot (which would be a genre shift). Now where will it go?