Pissing.

Pissing. All of them are always pissing. The babies are always pissing if they're eating, happy, scared, asleep, talking, etc. I've never seen anything piss so much. Why are they pissing? WHY ARE THEY ALWAYS PISSING?

No bladder

Because Kiriraitaa wanted to piss people off and it became a trend.

They are actually portals to the sugar-water dimension

Because yukkuri are always overflowing with happiness, of course.

I agree its probably to piss you off

pissing is a gesture of supreme easiness

a level that humans can never hope to attain