Pap Monster Card buff actually gives 2x Drop

Once you complete the set you can never get the buff again. Even if you pick the card up you get a message saying something like "your book is full and the card will disappear."

 Spoiler

You don't get the buff even if you pick up the card (as evidenced, if the buff were given, the monster book buff on top of the screen would be renewed).

Oh well, so long for hunting drum bunnies with the free 2x drop. >_>

By the way, can someone extract the buffs that each monster gives with it's card? Such a list would be pretty useful.