Center letter: o
Outer letter: b f g l r u
Answers (32):
  bullfrog
  blob
  blog
  boffo
  boll
  bolo
  boob
  booboo
  boor
  burgoo
  burro
  flog
  floor
  flour
  fool
  forgo
  foul
  four
  frog
  froufrou
  furor
  glob
  golf
  goof
  googol
  grog
  lobo
  logo
  logroll
  loll
  roll
  roof