Some C&C...

The pain.

The betrayal.

The sadness.

These thoughts invaded Ryouga's mind as he tried to
sort out the madness
that just happen right before his eyes.

That just happened
 

"Damn you, Ranma!", Ryouga swored.

There should be no comma after "damn you, Ranma!"
Ryouga  swore

"Why did you...why did you do it?!"

***flashback sequence***

Ranma laughed as he hammered Ryouga with his
patented `Chestnuts
Roasting on an Open Fire' technique. Ryouga, as
usual, absorbs the
damage and predictably gets angrier.

Two things: the attack isn't really patented, and if
it is, the copyright belongs to Cologne, not Ranma. ;)

Also, the beginning of that paragraph is in past
tense, while the end is in present.  I'd suggest
picking one or the other and sticking with it. 
(Preferably past, since this *is* a flashback.)

It was a normal typical fight in the empty lot near
the Tendo Dojo.
Blows were exchanged between the two martial
artists. Both were trying
to overcome the other with various of moves and
counters.

"Stop moving, coward!", Ryouga roared. Ranma smirked

No comma after "Stop moving, coward!".

as he continued to
evade Ryouga's powerful strikes. His evasion was
bringing him closer to
the street.

*flashback sequence end*

Now it's past tense again.  Unify your tone.
 

Why didn't he dodge... why did he just... but he
didn't dodge. And now
his companion was gone. He didn't even have a chance
to say goodbye.
Forever lost like himself.

"Curse you, Ranma!", Ryouga yelled.

Curse you Ranma!  Why didn't you let me hit you! ;)
(No comma after "Corse you, Ranma!"...)

Ryouga kneeled down next to his crushed companion.
If only I was a bit
faster. This would never had happen...

If only I was a little faster!  Then *I* could've been
the one who killed Ranma!  Oh, why did this happen? 
Why?  I wanted to kill him so much!

***second flashback sequence***

Ranma continued with his evasion tactics and all the
while with a smirk
on his face and an occasional laugh. Ryouga was
filled with rage as he
also continued to try to catch the elusive martial
artist in the attempt
to pummel him to a pulp.

"Bakusai Tenkatsu!", Ryouga roared as he drove his

Bakusai Tenketsu
No comma after "Bakusai Tenketsu!"

finger into the
ground at Ranma's feet activating his patented
`Breaking Point'
technique to try to blindside his opponent to gain
an advantage. But
Ranma anticipated this and jumped backwards into the
street.

Smart boy.

Ryouga screamed in rage at this miss and grabbed for
his umbrella. At
the corner of his eye, his mind noticed the imcoming

suggestion: From the corner of his eye

steamroller coming
towards Ranma on the street, but he ignored it and
launched his
umbrella, head first, towards Ranma.

Ranma, oblivious to the incoming danger, saw the
umbrella launched at
him with speed and power that he knew would hurt him
if he stood still.

Ryouga, after he threw the umbrella, immediately
noticed the speeding
steamroller that was about to run Ranma down and
started to yell at
Ranma to move. Ranma, for the most part, was still
oblivious and was
only concerned with the incoming umbrella that was
hurtling towards him
like a missile.

Time slowed down.

Ryouga started forward yelling for Ranma to move.

The steamroller began to honk its horns but still
driving towards Ranma.

No sense braking!  It's only a pedestrian!

Ranma prepared to deal with the impending threat of
an umbrella.

Squeals were heard as the steamroller tried to put
on the brakes but the
road was still wet from yesterday's storm and it
started to slide.

You might want to tell us there was storm in the
beginning of the fic, instead of at this point. 
Otherwise it seems contrived.

Ranma sensed the other danger immediately. He

Ranma sensed the other danger immediately! All the
steamroller had to do was honk its horn a few dozen
times.  After all, it had only been coming towards
Ranma for the last minute or so. ;)

blocked the umbrella,
numbing his arm dued to the power behind the throw

Numbing his arm?  Can someone do that?
Numbing his arm _due_ to the power

and turned to deal
with the other threat.

"Ranmaaaaaaaaa!!!", Ryouga screamed.

No comma after "Ranmaaaaaaa!!!" 

Crushing sounds were heard and then no more...

***second flashback sequence end***

"Shi Shi Hokodan!", Ryouga thundered as all that
pent-up depression he
had stored was launched into the air leaving himself
drained.

leaving him drained
No comma after "Shi Shi Hokodan!"

"Geez, chill out, Ryouga. It was only a stupid
umbrella. I'll buy you a
new one. Sheesh.", came the voice of Ranma from
behind Ryouga.

The period after "Sheesh" should be a comma.  The
comma should be within the quotation marks.
 

"I'll make you pay dearly for destroying my
umbrella, Ranma!", answered

Comma within quotation marks...

Ryouga as he launched himself at Ranma. Ranma
laughed and began to dodge
once again.

And they began their merry little fight over
again...

How nice.
 
:)
_________________________________________________________
Do You Yahoo!?
Get your free @yahoo.com address at http://mail.yahoo.com