Hungry Postman?

At first look I'm sure you must be thinking we have a mad dog and the little devil has chewed up one of my letters! But no. We only have Frog the Cat and she spends most of her day asleep! I started to think maybe the postman was chased by a wild Rottweiler!! Snarling teeth, slobber spraying in all directions. But no, this is how this ATc swap arrived yesterday completely ripped to shreds! A great mouth full gorged out of one side and tiny little teeth marks everywhere. Luckily one ATC and returning envelope arrived undamaged, but it does makes you wonder what they get up to down at the post office... a bit of postman's knock perhaps?