Is it possible to be de-lvl'd or given a monster book card?

Unfortunately this is a cold hard no. I tried asking for a delevel on my gpq mule but was declined.

 

Hey, at least you got 4/5! Most people... don't.

 

OP at 4/5 while most of my characters are 0/5

 

I know edging is fun but make sure your exp is always below 50% next time

 

Just remake your character.

 

There is an NPC that sells PQ boss cards for 10m per card (or 5m plus a bunch of etcs)

 

When you get Cube Slime cards in Magatia, be sure to keep 200 of the etc drop and then go to Night Market with 5 million mesos.

I have to do it this way because all of my characters were 3rd Job when Monster Book came out - so I didn't even get the opportunity you did! =o)