These are stickers that were given away for a limited two-day period at 551 Horai. ꒰ღ˘◡˘ற꒱ There are two types: puffy stickers and adult encyclopedia stickers, both attached to a backing sheet designed to look like a pork bun box♪ These are no longer available! ♪(´ε｀ ) Since I received them, there's a slight crease on the backing sheet, but it doesn't affect the stickers themselves, and it's barely noticeable. ꒰ღ˘◡˘ற꒱ I will sandwich them between cardboard and ship them in a plastic envelope♪