V, whose full name is Kim Taehyung, was the one who said “Borahae” during BTS’ third muster. It was the BTS annual fan meeting held back in November of 2016. The moment when purple light sparkled the audience, V explained what does I purple you mean.

“Do you know what does color purple means? Purple is the last color of the rainbow colors, so it means I will trust and love you for a long time,”

Other BTS members and ARMY were so impressed. V knew this, but then he admitted that he was just kidding.
“I just made it up,”

Yet, he continued talking about the significance behind the color and it related to his love for fans. V said.

“I wish I can see you for a long time, just like the Borahae means. We’ll always trust you and go up the stairs with you,”

Since then, Army welcomed purple as BTS’ color, and their way of telling BTS how much they love them. It became BTS purple. From that point, it is just BTS color unofficially. Just like the army, BTS also uses this phrase to show their love for ARMY. BTS army always hears BTS members saying the line during their ending speeches at their concerts or during their award show speeches. Every time they say it, the army knows BTS is thanking them for their support and love.