I can't really answer that, seeing how there isn't a complete translation for the manga yet (i'm not even sure whether the manga reached it's end), but i don't think that there are many diffrences, if any. since the ending of "Seiji goes and takes Midori to a date" is pretty much the only possible ending for the story...


however, the manga has alot of funny parts, including Kouta falling in love with Seiji (or something close to that), the amrican transfer student who's in love with seiji, and the mad doctor who wantsto cut of Midori...
it's real good stuff, keeps you laughing for hours..