The Blue Pillow is a pillow obtainable in the store/pillows page in PFS. The pillow has a blue feathers design on the pillow with blue feathers also being particles emitted.
Somebody was clearly bored with their free edition pillow. So I guess, they decided to dye it in a wonderful blue. And market it for the greater good of seeing kids fight each other to the death with it.
I guess this makes it a red pillow. Because of Jimmy's blood.