panty-less; wearing no underwear
Colloquial wasei-eigo term for going without panties or underwear, often used in casual or humorous contexts.
wasei-eigo (Japanese-coined English), from no panties
It was hot today, so I went without underwear.
ノーパンでスカートを履くのはちょっと勇気がいる。
Wearing a skirt without panties takes a bit of courage.