Someone who has a fetish for having feet in their mouth, all they want is feet, all they think about is feet and the one place they want to put the feet. A foot mouther also love having people putting their feet in others mouths
Man: I must be honest with you, please don't bully me
Woman: say what you must
Man: Before we bone each other I must confess I am a foot mouther
Woman: OMG ME TOO, lets be foot mouther's together and suck each others feet.