Responses
What do you mean by that? I don't get it. Anyway, here's the page I'm referring to. I don't understand korean but it seems to me that they are finding out each other's birthyear.
(spoilers, obviously)
https://toonkor.com/data/file/wtoon/15150281462604.jpg
Siblings with a 20+ years gap exist and sure, this may be more or less common depending on where you come from but not unrealistic at all.
Here's another link https://i.imgur.com/bffSoi4.jpg
Lol, I don't think Oppa is that old, he might be only 10 year older from the guy, which is not that old. XD
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