River Rat

You learned to swim right
after you learned to walk. When you were a youth, a gang
of river pirates put you to work swimming in nighttime
rivers and canals with a dagger between your teeth so you
could sever the anchor ropes of merchant vessels. You
gain a +1 trait bonus on damage rolls with a dagger and
a +1 trait bonus on Swim checks. Swim is always a class
skill for you.