The footpussy is created by placing the soles of a woman's feet together, creating an opening between the arches of the feet that somewhat resembles a pussy. There are many variations to the footpussy, but the crucial element is the opening between the soles of the feet. This opening can then be lubricated, and fucked, by sliding your cock between the soles of the feet. This would in turn, make you a footfucker. The owner of the feet would, in turn, be giving you a footjob.
Dude, I fucked the shit out of Stacey's footpussy last night. She has the sexiest feet I have ever seen. They looked even sexier covered in my cum.