The brothers boy bsf didn't confess bc he knows he had a gf and the boy bsf of the brother admitted to the uke that he liked his brother after he died or after the crash outside their house? If I remember still
This one? Og friend didn't like brother that way in this but uke thought seme do
https://www.mangago.zone/read-manga/nakanai_hibari/
Unfortunately its not a manga
You might have mixed up things then it's this omegaverse where uke's brother died on bike with accident with his paired omega then best friend told uke that he loved his brother but enbed confessed -
https://www.mangago.zone/read-manga/reversal_bl_haven_scans/
Does anyone know a bl where the uke had a brother and the brother got into a motorcycle crash (a truck hit them ig?) (The brother got into a motorcycle crash w/ his gf btw) And then the brother has a boy bestfriend who liked him. I think they were running away (ps. Not a side story cuz the brother died? I think)