When you're with your group of friends and they all start cornering you by being annoying, twelving is the perfect word to use.
It was a play on words to mean annoying. Since 'twelve' in Korean is shipi (ìì´) and 'annoying' is shibi (ìë¹), it was a clever way to combine the two for a whole new word. (Credits to Koreaboo)
Made by Kim Mingyu of SEVENTEEN !!
B: you're late again lol
C: i bet you spent all night playing games again
D: didn't redacted broke up with you becau--
A: why are you guys twelving already?