Responses
Nono that was just kind of a bad way to translate those consecutive bubbles. They used noona and dongsaeng there but they're definitely not related in context as far as I've read the raws. Not sure if they'll ever throw us that kind of twist in the future though but there wasn't anything before that pertains to them being related. Only Yeonji and Wonho were revealed to be siblings so far.
Bro, Youngchan is so misunderstood. Just cos you are afraid of his massive statue doesn't mean he is a bad dude. He is like one of the greenest flag semes in yaoi and he would be a great dude if he was real too.