You can wipe leather couches clean with a damp cloth, but removing the stain from an upholstered fabric couch requires a more determined effort.
Soak Up the Oil
Double up two paper towels and either heat them for a few seconds in the microwave, or hold them against a warm radiator or kettle for 30 seconds. Be careful not to burn yourself. Press the paper towels firmly onto the greasy stain. This will warm the oil in the peanut butter and make it easier to transfer to the absorbent paper towels. Repeat this step three or four times until the paper towels no longer absorb any oil.
Disolve the Stain
Add 1/4 cup of laundry detergent to a salad bowl of warm water. Use a sponge to gently dab the stain. As the detergent mixes with the oil, it will cause the stain to gradually lift from the surface. Take care not to rub or scrub at the stain as this could damage the couch.
Dry the Coach
Once the stain has lifted, shake corn flour on to the area to absorb any remaining moisture or oiliness, then brush off with a soft bristled brush. The couch should now look as good as new.