I had a similar problem, but it was melted chocolate. I was able to clean the surface of the seat, but all the little holes made it very easy to see that something had spilled. I took a toothpick and poked each hole, cleaning the toothpick with a wet rag after each poke. I had to do the entire area a few times--tedious but it worked.

 

came very close to that happening in my car this winter. glad it didnt. good luck with the clean!

 

it will haunt me for life as long as i still own it. see if you could order a new chair and replace the old one and have your friend pay for it.

 

The same happened to me when my son threw up in the back seat as the result of stomach flu. I managed to get it out through multiply scrubbings with a damp cloth. Had to kind of force water into the little holes by squeezing the soaked cloth then wiping forcefully.

 

Here is what you do. Make sure it is fully dried (I am sure it is by now), and take a toothpick (the pointy kind they have at restaurants, not the cheap flat ones). Poke through the hole, and punch all that crap out. From there, use a fairly damp cloth and wipe over the spot and repeat the process. Do this about 2-3 times and it should be gone. We were on a road trip and my friend dropped some chocolate under his butt without knowing it. We got out to get a bit to eat and there it was. At first i though he S!@# himself but it was just chocolate and we were able to get it out right in the parking lot using the toothpick from the restaurant.