Ok, yes, I know.
Today was going to be dropper beetles, but I realised its Monster of the Day 42 and I couldn't not. Sorry.
Don't panic.
Improbability levels now 1 to 1. We have normality, I repeat, we have normality. Anything you still can't cope with is therefore your own problem. Normal service will be resumed tomorrow, destruction of the Earth by Vogons permitting.
For more invaluable information on this fascinating species, see: Mattresses and Mattress
Mattress
by Cab Davidson
Stat Mattress AC: 9 HD: 4* Movement (Flolloping): 90' (30') Attacks: 1 willomie Damage: 1d4 or smother No. Appearing: 0 (1d8) Save As: Fighter 4 Morale: 7 Treasure Type: Nil Intelligence: 5 Alignment: Neutral XP Value: 100 In an infinite multiverse, anything is possible. If you can think if it, it probably exists on a distant world, in a strange outer plane, or brought into being via. the febrile imaginings of a nameless immortal.
Mattresses are friendly, dim-witted, docile creatures capable of speech. They are all called Zem and live in the swamps of Sqornshellous Zeta. Many of them are slaughtered, dried out, and shipped around the galaxy to be slept on by grateful customers, though they do not appear to mind this, one noting that since they are all called Zem they never know which of them have been killed anyway so their concern and grief - "globbering" - is kept to a minimum.
They are unlikely to cause offence, let alone attack, but if forced into a fight they will attempt to willomie their aggressor, by rising up on their rearmost springs and flolloping on top. A human sized or smaller foe must make a save vs. paralysis or be driven into the mud, where the saddened, globbering mattress will attempt to smother their victim, inflicting 1d4 damage each round (although a further saving throw can be made once per round to escape).
Mattresses do not covet treasure, but can, if bludgeoned to death and sufficiently dried, be sold as quality bedroom furnture.