yes
when chapter did this happen wtf i don't have a good memory
they js show a glimpse of it tho like in the starting chapters
I don't think it's his twin brother because when Seo In went to the birthday funeral of his brother .... His granny told someone of the family that you can't blame Seo In to try having a good relationship with someone who is not related to him by blood...
So we can 100% assume that Seo In and the other brother were not related by blood at all.
Yeah but it still weird despite them not being blood related…
prolly step brother or smthg
So the person Seo kissed was his goddamn twin brother..?