Evergreen
yes!
Should I Write You a Love Letter Instead?
Sweetie, Sweetie, Sweetie
The Duke's Plush Obsession
I Can See Your Stats!
Raising the Demonic Cult's Leader
Reincarnated into Demon King Evelogia's World
Stuck in My Sister's Dating Sim
Don't Press the Button
To deny the route
Secretary Jin's Confinement Diary
The Mutual Non-Aggression Is Unpalatable
Thank you guys!!!
yes it has been a very popular bl subgenre over the years
the ones i can remember on top of my head are:
https://www.mangago.me/read-manga/kyou_kara_maoh/ (old but gold, has anime adaptation too)
https://www.mangago.me/read-manga/reincarnated_into_demon_king_evelogia_s_world/
https://www.mangago.me/read-manga/kiss_the_abyss/
https://www.mangago.me/read-manga/turning/ (personal favourite)
Isekai BLs, do they exist?