dirty feet

I CANNOT GET MY FEET CLEAN!

City grime has kept the bottoms of my feet filthy and I can't figure out how to fix it. It's not like they're actually that dirty - when I walk on the bathmat, there's no dirt, but for whatever reason, they keep looking gross.

Suggestions are appreciated.

Also, this accidental picture (I was trying to get out the window) was almost the blip du jour but I thought it looked a little too weird.