The Lucky Poop
The Lucky Poop is a secret character. I never quite believed it, but I actually got it one day! You can't do anything with it except to send it back home by pressing the b button.
How to get it: I read this from other sites. The key is to neglect. I started up the angel, then I ignored it completely from the time I started it. (don't feed, play, flush, turn off the lights etc. Don't touch any buttons, don't do anything.) A few times I got the old man angel instead, but one day, poof! I see this faceless poop before me!
It is rather disgusting that a poop is a lucky character, but oh well... Anyway, the Japanese version has a face, the American version doesn't.
That's all there is to it. Just these two scenes where you see a poop bouncing around. (how fun can that be?.....)