Believe it or not, Taehyung's 'I purple you' phrase has now been so popular all around the world. As you might have known, it's a special word used by Taehyung to express his love to his fans. He first said it to ARMYs at a fan meeting held in November 2016.
During the fan meeting, Taehyung asked his fans, "Guys, do you know the meaning of the colour purple? Purple is the last colour of the rainbow colours. Thus, it means I will trust and love you for a long time. I made it just now. Just like that meaning, I hope we can see each other like now for a long time."
As time goes by, the word itself is getting more popular, not only among ARMYs and K-pop fans but also among everyone who has limited knowledge of K-pop