Yes, I payed extra for that and it costed ALOT when consider I have high naturall strenght score. But whit trick form Exotic Weapon Master I can double the strenght mod in damage whit my whip and treat it as two-handed weapon for power attack purpose. Oh yes, I have also fiendish servant. But mine is a Nessian Hellhound (stoled puppy from kennels of Asmodeus himsefl :D). Of course if DM allows it of course, otherwise I would bend forwards into a fiendish constrictor snake.