Eh, well. This
is a kinda ambiguous topic, but I'll give it a try, at least... But I can't make a definite decision as to who the
most "tragic" character is...
Obviously, OAV Ifurita hasn't led an extraordinarily happy life. Given that she was created as a weapon (who, although she claims to have no emotions up until Makoto lays the mack on her, clearly does) and probably logically treated as such, well... that's gotta start to hurt after a couple hundred years. Add to this the much-discussed possibility that she was made anatomically correct for all the wrong reasons, and you've got yourself a pretty tough life.
On that "emotions" note, I just thought that it's really very sad to think that OAV Ifurita maybe started out, personality-wise, like TV Ifurita. Er, well. Not
quite so... enthusiastic, but you get my drift. Adds a horrible perspective of shattered innocence and all that other angst-fuel. :-/
OAV Rune... yeah, she seems pretty lonely. I won't elaborate much more than that, given that we've discussed her in her TV vs. OAV topic.
Then there's Makoto and all the women who want his smooth, virginal backside. ...ahem. I see you gents looking at me like that, but hear me out. ^^ It must get at least a
little stressful to have so many admirers all at once... Though is mainly taken from the real-life instance of Makoto I know, who in spite of being surrounded by smart, beautiful, and fun girls
(me being one of them... I think I'd be the Shayla in this case?
), tends to express a certain measure of irritation that cracks the "it's okay" facade that they both seem to share. A sort of "I'll bloody well pick who I want when I want, so back the hell off" attitude.

Who knows?
Jinnai? Eheh. Well, color me biased, but I'm afraid I beg to differ on this one. I wouldn't consider the guy a loser at all!

Contributing factors aside :|, he
did wind up the School President... And could a loser hold his own when going from a relatively normal high-school life to becoming the backbone of an
empire? Nice rebound, I say. And what can I say? Much as it pains me to say so, the reason why Jinnai's not getting any is probably because he doesn't
want any. That said, his being one of only two human(-seeming) creatures in the Bugrom Empire notwithstanding, I won't hesitate to add that power is a definite turn-on for a loooot of women. Not all, certainly, but a respectable number. |D
I've tried to figure out numerous times what the nature of Nanami and Jinnai's relationship is, exactly. Do they genuinely despise each other? Or do they just share the common sibling rivalry/mutual annoyance thing? Not having any siblings myself, I couldn't relate very well... though I doubt I'd be able to anyway, due to their extreme circumstances.

In any case, neither of them seem to be real torn up about it.
And sure, Jinnai's probably hopelessly, irreversably insane, but wherever he may be, he seems pretty damn happy there.

That's a definite mark against him as a tragic character, at least in his personal attitudes, I think. Of course, it's probably a whole different issue if you wanna get all moral and stuff, but where's the fun in morality?

In fact, I think I'd even go as far to say that Jinnai's one of the
least tragic characters in the series because in spite of teh crazy, he loves what he does.
... *looks up at the other-people-to-Jinnai ratio* Uh. Well, I
did say I was biased.
On a wholly unrelated note: *muffles giggles at her shiny new avatar and runs off like a little girl who's heard her first dirty joke*