I'm proofreading a script for a visual novel, and came across a little issue. If you want to emulate an elongated "oo" exclamation in human speech, what kind of spelling would you use? I've come across two ways of spelling it: "Ouu" or "Ooh".
For reference, this is the sound that I'm looking for:
https://www.youtube.com/watch?v=8TQ-gD4UCmI#t=143
I'm not finding it easy to search on recommended spelling for these exclamations, so any help would be great!