who the heck is pionaur?

I remember seeing a tiktok of the le sserafim girlies repeating the “where the heck is saki?”line from 1-800-hot-and-fun. then they said “where the heck is pionaur/peiner/however u spell it”. I was wondering… who the heck is pionaur? I know their fandom name is “fearnots” and in korean it could sound.. kinda like it?? but is this like a reference only people deep into le sserafim know? or?

edit: the tiktok if yall were wondering https://www.tiktok.com/t/ZP88jMPFV/