Recently I have met many Korean friends my age which is cool, 'cos I mostly meet 동생 or 오빠
At a meetup yesterday, I also met a 동갑 but when I told him we are 동갑, he was shocked! I asked whether I looked older than that and he said actually he was about to tell me to call him 오빠 ㅋㅋㅋ
How cool!