[NLS8520]

Here is how I would tackle the stain. I would first vacuum the entire seat with a soft brush attachment. Then get two all purpose short nap microfiber towels, and some upholstery cleaner I have used Sonax upholstery cleaner with good results. I would wet one towel with very hot water and wring it out until its JUST damp. Lightly mist a section of the towel with a few light spritz's of the cleaner and very gently and slowly dab the cleaner on the seat then gentle wipe turning to a clean side and applying a few additional light spritz's of the cleaner as needed until its clean then take the second cloth and dab it dry. One thing to note, the clean section may appear different , ie cleaner than the remainder of the seat depending how dirty they are so you may have to clean an expanded area or you can clean the entire seat with that method. Hopefully by using the diluted method with the wet towel you can get around that though. Good luck keep your friend out of your car until he gets some respect.