>>281756322
In the VN she goes UMYAAAAAAAAAAAAA a couple times, like when you beat her at Shimamon, but otherwise she didn't do it much until she started regressing.
For reference, this is the Umi in the regular common route right before Alka and she's already making sounds.
https://www.youtube.com/watch?v=AafRN4IiyIY

I'm already starting to feel emotional at the Umi scenes, I don't think I'll keep my composure near the end.