Douglas MacDougall wrote:

"No, she did not," Kodachi replied, knowing full well that the doctor
would believe none of what she would tell him, and not caring. "It was
written by the ones who abducted Ranma, left behind to allay
suspicions."

As I was reading this, I was wondering why she didn't believe that
the note *was* real, but that Ranma wasn't a... shall we say, willing
participant?  Then I remembered the intro story.  Maybe you should
recap the relevant scene from the intro somehere?

[...]

"Tell me more about Ranma." The doctor opened a file folder and looked
through it. "I understand that you and he dated."

"Once, yes. I had made a wager with my rival, Asuka Saginomiya, the
White Lily, as to which of us could obtain the finest date for the
evening. Ranma was merely helping me win the bet."

Kodachi seems to be belittling her relationship with Ranma.  He was
*merely* helping her with the bet?  They only dated *once*?

Maybe "officially", but they've been together many other times.  This
makes it sound like Ranma is a non-romantic friend was just doing her
a favor one time, and there was nothing more to it than that.

That's because this Kodachi is smart and doesn't want the doctor to
think that she's obsessed and delusory on the subject of Ranma.

The shrill, maniacal laugh resonated through the air, chilling him to
the bone. "Ohohohohohohohohohoho!" Tonma reached for his gun, but was

I much prefer "lyrical" to maniacal.  ^o^  Melodious?  Terpsichorean?

grating?

much too slow. A flurry of club blows rained down onto his head, making
a sound like popcorn bursting, and he slumped to the ground,
unconscious.

technical point:  Has Kodachi ever thrown her clubs?  I would assume
she'd use her ribbon, or throw a ball.

Yes.  Most notably, the "Attack of a Thousand Clubs", where she essentially
juggles her clubs off her opponents head.  

Tanaka moved ahead to where he could see her. The Black Rose. He'd
never seen her in person before. Her hair was bunched together in a
single ponytail on her left side. The green and black leotard she wore
shimmered in the sunlight. And her eyes glowed with such determination
and confidence that her stare almost seemed to burn him.

suggest: Her hair was gathered into a single ponytail that hung off
the left side of the head.
("Bunched together" sounds like how a crude odango/meatball would be
made.)

[...]

Before Tanaka had even noticed her arm move, the Black Rose's ribbon
lashed out. Like a frog's tongue gobbling up an insect, it took hold of
his weapon and pulled it from his grasp, landing it deftly into
Abujima's hands.

Good imagery, up until the point when the "frog" doesn't gobble up the
insect, but gives it to Abujima.

Actually I think "snatching" or "snaring" would work better.  Frogs don't
gobble with their tongues.  

[...]

The Black Rose smiled at him. "I understand that you and I have mutual
enemies; the aliens who call themselves Fellani. Shall we go somewhere
and pool our information?"

You and I have mutual enemies: the aliens
or
You and I have mutual enemies, the aliens
(The second clause isn't independent.)

Are we forgetting someone?  Tonma is out cold, but Tanaka is still
standing there, watching this whole conversation taking place.  

Well, after hearing that conversation at least he'll be assured of
the Black Rose's sanity.  

He

could still pick up his gun, tail Abujima, etc.

Summary:

The grammar errors I found were all pretty technical, and not terribly
important.  There did seem to be a slight excess of sentences starting
with "but", which I didn't mention above.  I normally don't mind too
much, but this informal construct appeared somewhat out of place amidst
the otherwise formal language you used.

This was a pretty good introduction to Kodachi's section of SSOA.  You
established that Kodachi was institutionalized, and has been out of the
picture for weeks.  I would have liked to have seen a minor recap of
Akane's abduction, though.

I'm wondering what the deal is with Kodachi's rescuers.  It's pretty
ambitious for high-schoolers to arrange a break-out. (Made possible
by Sriipi-Taimu sleeping gas.  Endorsed by Kodachi Kuno.)  And why
did it take them weeks before they acted?  For that matter, am I even

Maybe it took that long for Kodachi to smuggle out a message to the St.
Hebereke Gym Team.  

right in assuming they're classmates?  Hopefully this will be addressed
in your main storyline.