我的同事說用 WD40 (home depot, walmart etc) 可能會有意想不到的效果:
噴上 WD40, wait 15 mins, then use the regular detergent or carpet cleaning things and water to wipe the area out. But he said that's mainly for oil type of stain. wouldn't hurt to try.
我從來沒機會試過, 要是用了的話請上來報告一下哈.