One and one = 'oh noooo!'

On Monday, the Smoking guard I spoke of earlier told me:

"Teacher, Friday, Saturday, Sunday I drink-uh soju!"
"Why?"
"Birthhhday! oh yeahh!"
"oh..."
"Yeaaaa! Sunday...my head-uh ohhh noooo"
"Soju...and?...what?"
"One samgyupsal [mimics wrapping a piece and popping it in his mouth].......then!....one soju! ohhhh noooo!"
"One and one?"
"Yeah! One...and one...is-uh ohhh noooo!"