I own several opening credit cels from Gokudo.  
When I bought them, they all came with sketches, 
but none of the sketches were matching; they were 
all far-off sequence numbers.

Well, somehow over time I forgot that I had 
sketches for these cels, and in my mind they 
were "naked" -- sketchless.

An auction came up on Yahoo Japan for a set of 
Gokodu opening sequence sketches.  I 
thought "Well, at least I can get SOME sketches, 
although they won't be matching".

I won the auction, and a few weeks later the 
sketches showed up, and you can probably figure 
out the ending.

When I went to file the sketches, I discovered 
that I already HAD non-matching sketches for all 
the cels.  DAMN!  WHAT DID I DO?  I JUST BOUGHT 
NON-MATCHING SKETCHES TO SUPPLEMENT THE NON-
MATCHING SKETCHES I ALREADY HAVE!

Then, wait a minute, I said -- the sequence 
number of this sketch that I just bought matches 
the sequence number of the cel I bought a long 
time ago!  And that other sketch matches!  And....

And the packet of sketches I bought on YJP was a 
perfect match for the cels I had bought some time 
before with the mismatched sketches.

I went back and checked my records, and it was 
NOT the same seller on YJP.  Both are well-known 
sellers, and they were different.

And so now I have matching cels and sketches from 
the opening credits.  What's the chance of that 
happening?

BTW, aren't there any Gokudo fans besides me?  
I've been trying to sell my secondary, extra set 
of unmatched opening sequence sketches for a 
pretty cheap price, and I seem to be the only 
person in the world who likes this show...