You don't need to feel weird about it, cause brother-sister doesn't always mean as in the sibling route. It's just in Asia region, we have a certain habt to address someone older/younger. In this case, it's just a simple dongsaeng (means little bro/sis). Also if you think about it, kids that age doesn't really understand the concept of 'like/love' to other people. Yeah, hope you understand what I type
I get what you mean. I am also an asian so i understand and is familiar with things like this...... It just, they were giving such strong sibling vibes toh.... to me, even though i know Mikhail is ML.
Maybe its just me feeling those sibling vibe. The English translation often set lines for me. I don't mind with other brother terms but the English Brother word automatically switch my perspective to real Sibling bond..... You know, can't let myself jump on real sibling bond and take it as romantically ...... Plus, with the european ambience setting, it's hard to see it in asian way.

Wait!! I thought Mikhail was our ML so why is this going brother-Sister route. They are already thinking of each other as brother Sister...... This feels weird.