Tools Link
http://shenmuesubs.sourceforge.net/download/Using PVR Dissector you can blast through all the folder directorys and extract all the PVRs /PNGs and then using windows search identify what is where quite easily
Ryo's files are called YKB/YKC/YKD/YKE/YKF Found in Chara Folders & Humans.AFS (You will want AFS extractor too)
Typically :
disc1\scene\01\model\chara
&
disc1\scene\01\Stream\Humans.AFS (You may also want AFS extractor too)