Before you click away after seeing "gender bender" as a tag, let me say that this is NOT YAOI and NOT SHOUNEN-AI. It is simply a story of a guy who fights his instincts over the kawaii that is supposedly another guy.
The comedy is spot-on, but of course they all rely on the premise that Aikawa (the ambiguously gendered deuteragonist) is a guy. However, it is never confirmed. Hence, Maki (our hero) is stuck being teased over and over again by Aikawa and being harassed and envied by all the males in the school. This inevitably leads to both jaw-droppingly fantastic and belly-achingly hilarious situations. An odd couple they are (a couple meaning simply two people together of course), but they chemistry as a comedy duo cannot be underestimated.
However, under the gag comedy is a layer of questioning that isn't really dealt with in typical shounen mange. Is Aikawa actually a guy? Does it really matter? Should it really matter? Being a shounen, it simply scratches the surface of the delicate topic of sexual orientation, but it scratches it well. I am a straight male and have personally never been interested in or read yaoi or shounen-ai, yet I found their drama strangely touching, probably due to the fact that their relationship can never quite approach the romantic stage. It's quite interesting to see two people interested in each other but refusing to look at each other romantically yet still maintaining a casual friendly relationship. Translation: no rage-worthy angst here.
I've read many gender benders before in my journey across the land of shounen, but I can confidently say that there is no other manga like this. If you like shounen, particularly romcom shounens, you WILL enjoy this. Read it for the comedy or read it for the peculiarities, you will not regret it.