consider genshiken, started mostly as an otaku comedy, transitioned into a boring rom com in 2nd generation with new quastionable characters, some trap and cross dressing tendencies and turned into a cheating drama involving a transgender (but in a different series, like in an alt story/ending, wich originally wasnt even about genshiken), its something like
genshiken ->
genshiken nidaime ->
spotted flower
well, guess its not a bl, but still a fiesta and seems people have mostly negative reactions in the comments, if not mixed