angsty manga in par with 10 yrs that i loved you. not necessary that it's yaoi it just needs to angst driven ლ(´ڡ`ლ)
Not as sad as 10ywilytm but these made me cried a river
http://www.mangago.zone/read-manga/1866/
http://www.mangago.zone/read-manga/december_rain/
http://www.mangago.zone/read-manga/incidentally_living_together/
http://www.mangago.zone/read-manga/cocoon_of_the_heart/
Plot is, bot is isekaid to a game (which turns out the plot is now a fanfic of the actual game). He was isekaid as a black dragon for a royal family. He meets top (golden hair) and he was pretending to be n omega. Time skip. Everyone thinks bot is an alpha and the top is an omega.
Thanksssss.
https://www.mangago.zone/read-manga/i_was_reborn_as_his_highness_the_prince_s_little_evil_dragon_shonen_ai/
Thank u mah friend ლ(´ڡ`ლ)