Responses
I think Dohyeon (the Hyung) just see him as a little brother cause Gyeol is always get into violence ever since he was in school and as you can see Dohyeon was scared when he remembered how Gyeol's anger and violent behavior...
So probably he's just being a protective big brother that worries about his little brother

You’d probably need to read chap 27 but I’ve been thinking for a while now, does his hyung maybe like Gyeol?? There definitely is such think as protective best friends but idk he just seems VERY involved in Geyols life