Traces
Your foot is a little red and you can see traces of ink streaked on it. Where did these traces come from?
せき
あと
None
Turns out the traces of red ink were from a sexy (せき) rave you were at last night. Everyone around you looked so sexy, with their glow-in-the-dark paint, so you decided to put some of the red ink on your feet so everyone could see your sexy dancing.