@Krulle, @rob, @Dragonrider, @EHines @agedsage: I was going to make him say "GAAH" again, but he's said that too much already. So "WAAH" seemed like a good alternative. He seems to be good at disrupting things (Tirin's concentration and the Mirror's private space). Let's hope he does more in the near future that will redeem his impetuous actions.
@Guesticus: I'm pretty sure balk (pronounced "bawk" or "baulk") does rhyme with talk (right?) Just wanted to play on old Daddy's wisdom --- imagine Tirin training, running through her excercises and old Dad spouting various words of wisdom to Tirin over and over again. Now in her first serious fight, she understands (or so she thinks).
@Merceneiress: Like said, personally pronounce them differently- "baulk" and "tawk", have never heard it pronounced "taulk"
Yeah, you never truly understand until you have to put what you have learnt in real practice, and 'play-fighting' (or training) never fully prepares you for the real thing
"EEYAAH!" is another good alternative
It's okay if you have Billy repeat himself, most people usually use the same exclamation when startled, unless you are Sydney Scoville Jnr, in which case what she says makes seasoned sailors blush :P