https://www.mangago.zone/read-manga/shounen_no_kyoukai/ It was at 9.0 at some point but not anymore.
This is already 9+ but I believe is underrated
https://www.mangago.zone/read-manga/theo/
https://www.mangago.zone/read-manga/ice_man/
https://www.mangago.zone/read-manga/macguffin/
https://www.mangago.zone/read-manga/koi_nanka_shitakunai/
https://www.mangago.zone/read-manga/the_man_next_door_is_a_vampire/
https://www.mangago.zone/read-manga/goodbye_lilac/
https://www.mangago.zone/read-manga/glen/
Distorted soul I see so much potential in this
what are some of your bl manga favs that you think SHOULD have a 9.0+ rating but doesn't