It's where your UNDERPANTS live.
The Big Bang Theory Season 9, Episode 10
I own nine pairs
of UNDERPANTS.
The Big Bang Theory Season 7, Episode 1
let all the boys see
my UNDERPANTS.
The Big Bang Theory Season 5, Episode 1
because you no longer
wear UNDERPANTS.
The Big Bang Theory Season 5, Episode 4
Instead of UNDERPANTS, I covered
my crotch with potato salad. Thoughts?
The Big Bang Theory Season 3, Episode 15