No one can believe someone as pure as you could be deceptive in any way. You have an air of innocence about you, and people have a hard time believing you could ever do anyone harm.
BENEFIT
When you make a Bluff check to tell a lie, your target always wants to believe you, granting you the standard +5 bonus on your Bluff check. This bonus only applies if the lie you tell is either believable or unlikely.