Because inactivity?

Whenn you don't respond or keep plurking, your karma drops. It's like in real life. When you just lay in bed, your karma will decrease

But your yingyang increases

funny I plurk, reply, add friends but still slowely decrease - just like in real life

LOL

Life's a bitch, then you Plurk

LMAO!

Don't take too much heed in it.