Minor change but I've received confirmation that Gang Junggu and Kim Seokjung probably speak Korean with Hyeonu so I'll be making some changes to the honorifics and how they are called when talking.
Kim Seokjung = uses a mixture of Brother (English) and dongsaeng (younger sibling) when talking to Hyeonu. I've been using a mixture of brother and little brother, but I'll probably change little brother to dongsaeng just to distinguish it more easily.
Hyeonu = calls both Kim Seokjung and Gang Junggu by Brother so far. I'll probably change it to 'hyung-nim' (older brother) from now on.
You can check out the glossary of common Korean terms linked in the chapters if you ever feel confused about any of these terms.