OK, so there's a lot of crazy / creepy / "cute" stationery out there in Japan, but in Tokyu Hands the other day I was handed this and was so mesmerised that I could not leave without buying it.

Immediately I thought "Oh, I'll send it to Bunny" but quickly decided that no, this is mine. The sheer terror of the other children being attacked by a personified baby's ass, the realisation on the face of the baby of his horrible alter ego... there's a solid internal logic to it that really appeals to me.
Also, on the back:

"Hello! Hello!"
"Run away!!"
I'll probably use it for accounts or something.