By the way, I don't think "Con" is supposed to be Contrabass, as it's pretty much the same as Wood bass, which is also listed for
that album.
It's more likely to be conductor, as the same kanji appeared on
this album, but there, conductor (most definitely) is abbreviated as "con
d".
Edit: A search for the actual reading (which is very likely to be "Kouji Haijima") brings up even more conductor results:
http://www.mobygames.com/game/ps3/de...dition/credits
http://www.mobygames.com/game/ps3/demons-souls/credits
http://vgmdb.net/search?do=results&id=132293