"Koo" from Koothrappali
and "PER" from CooPER.
The Big Bang Theory Season 9, Episode 12
As PER your suggestion,
we're hanging out.
The Big Bang Theory Season 4, Episode 5
You and I split
$2,000 PER ounce.
Breaking Bad Season 2, Episode 5
Per our roommate agreement,
kindly refrain from raucous laughter...
The Big Bang Theory Season 4, Episode 24
He was so busy figuring out
how many parts PER million of urine...
The Big Bang Theory Season 8, Episode 9