Sometimes human nature is a pain. Case in point, Kamomi-chan is plenty hot enough to get me off on her own. But when Hana-senpai is just sitting there watching, I naturally want more of her. Ahh, we came so close too. Toshi-kun! Why are you such an idiot?! Sigh. Is there more Hana-senpai somewhere? Yes there is! She shows up as an Exhibitionist Office Lady a couple years after this story with Kamomi-chan (so although this story is newer, it's set further back in time, and somehow she seems more mature in college than as an OL). If you want to read Hana-senpai as an office lady, prepare yourself for some unpleasant censoring and check out: Hanasan No Kyuujitsu.
(Despite that, I know if the roles were reversed, I'd be crying out for Kamomi-chan instead. There's just something about what you can't have....)