Cover the pen ink stain with a light coating of cornstarch. Allow the cornstarch to soak up the ink for at least 30 minutes before vacuuming it.
Wet a cotton ball with hairspray. Dab the cotton ball into the pen ink until the stain is completely gone. Soak a white cloth in water and gently remove the hairspray. If the stain is still visible, wet a white cloth with dry cleaning solution. Blot the cloth into the stain until completely gone. Avoid rubbing the cloth to further prevent embedding the ink stain into the suede couch fibers. Remove the dry cleaning solution with a wet cloth.
Allow the suede to dry before rubbing it gently with a soft bristle toothbrush to restore the nap.