If you drink liquor with just bottle, that looks like you're playing a trumpet. So they call it 병나발을 불다 (blowing a bottle trumpet) LOL If you're drinking soju bottle holding it in public, they'll call you, "저것 봐, 저사람 병나발 부네!(Look at that! That dude is blowing a bottle trumpet!)" Thanks it was funny!

And another word 나발(螺髮) is a buddhist term originated in the past from china, which is only for describing buddha statue. Curled up hair like snails. If you look at some buddha statue, you'll find the hair shaped like snails.

I am Korean, and have never seen this instrument before. It only plays one note. Very weird. https://www.youtube.com/watch?v=csevjEQhu4s