Okay, so I think I'm getting close to something here, thanks to Deszip and a little playing around myself.
I think that the six books cypher (LHFDMY/HDYLFM) combines with the HYPNO/DPTG clue: 467767 and LOOKINSIDE within The Painful Box somehow.
I've attemped both L4,H6,F7,D7,M6,Y7 and H4,D6,Y7,L7,F6,M7 but neither seemed to have done anything.
The only other thing I can think is that T&Bs reverse instruction refers to either the Cypher or the Numbers (As reversing the AV only gets "Lick my Ass" and "F*ck me in the pussy", which I don't think is a hint) but that's a lot of variables to test.


